--- a/libgui/src/color-picker.cc	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/color-picker.cc	Thu Apr 11 07:37:20 2019 -0400
@@ -39,7 +39,7 @@
   {
     m_color = old_color;
     setFlat (true);
-    setFocusPolicy (Qt::NoFocus);  // no focus, would changes the color
+    setFocusPolicy (Qt::NoFocus);  // no focus, would change the color
     update_button ();
     connect (this, SIGNAL (clicked (void)), SLOT (select_color (void)));
   }

--- a/libgui/src/documentation.cc	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/documentation.cc	Thu Apr 11 07:37:20 2019 -0400
@@ -559,15 +559,15 @@
         selected.append (selected_item);
       }
 
-      // Apply selection and move back to the beginning
-      m_doc_browser->setExtraSelections (selected);
-      m_doc_browser->moveCursor (QTextCursor::Start);
+    // Apply selection and move back to the beginning
+    m_doc_browser->setExtraSelections (selected);
+    m_doc_browser->moveCursor (QTextCursor::Start);
   }
 
   void documentation::notice_settings (const gui_settings *settings)
   {
-    // If m_help_engine is not defined, the object accessed by this method
-    // are not valid. Thus, just return in this case
+    // If m_help_engine is not defined, the objects accessed by this method
+    // are not valid.  Thus, just return in this case.
     if (! m_help_engine)
       return;
 
@@ -840,7 +840,7 @@
         QString title = m_doc_browser->historyTitle (prev_next*(i+1));
         title.remove (QRegExp ("\\s*\\(*GNU Octave \\(version [^\\)]*\\)[: \\)]*"));
 
-        // Sinve the title only contains the section name and not the
+        // Since the title only contains the section name and not the
         // specific anchor, extract the latter from the url and append
         // it to the title
         QString url = m_doc_browser->historyUrl (prev_next*(i+1)).toString ();
@@ -856,7 +856,7 @@
             anchor.remove ("Concept-Index_cp_letter-");
             anchor.replace ("-"," ");
 
-            // replace encoded special chars by there unencoded versions
+            // replace encoded special chars by their unencoded versions
             QRegExp rx = QRegExp ("_00([0-7][0-9a-f])");
             int pos = 0;
             while ((pos = rx.indexIn(anchor, pos)) != -1)

--- a/libgui/src/dw-main-window.cc	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/dw-main-window.cc	Thu Apr 11 07:37:20 2019 -0400
@@ -231,7 +231,7 @@
     if (ev->type () == QEvent::StyleChange)
       {
         // This might indicate un- or re-docking a widget: Make sure
-        // floating widget get a copy of our actions
+        // floating widgets get a copy of our actions
         for (int i = m_dw_list.length () - 1; i >= 0; i--)
           {
             // First remove possibly existing actions

--- a/libgui/src/files-dock-widget.cc	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/files-dock-widget.cc	Thu Apr 11 07:37:20 2019 -0400
@@ -226,7 +226,7 @@
     m_file_tree_view->setAnimated (true);
     m_file_tree_view->setToolTip (tr ("Double-click to open file/folder, right click for alternatives"));
 
-    // get sort column and order as well as cloumn state (order and width)
+    // get sort column and order as well as column state (order and width)
 
     m_file_tree_view->sortByColumn
       (settings->value (fb_sort_column).toInt (),
@@ -298,7 +298,7 @@
 
     setFocusProxy (m_current_directory);
 
-    m_sync_octave_dir = true;   // default, overwirtten with notice_settings ()
+    m_sync_octave_dir = true;   // default, overwritten with notice_settings ()
     m_octave_dir = "";
   }
 
@@ -390,8 +390,8 @@
             if (m_sync_octave_dir && set_octave_dir)
               process_set_current_dir (fileInfo.absoluteFilePath ());
 
-            // see if its in the list, and if it is,
-            // remove it and then, put at top of the list
+            // see if it's in the list, and if it is,
+            // remove it and then put at top of the list
             int index
               = m_current_directory->findText (fileInfo.absoluteFilePath ());
             if (index != -1)
@@ -726,7 +726,7 @@
           {
             if (info.isDir ())
               {
-                // see if direcory is empty
+                // see if directory is empty
                 QDir path (info.absoluteFilePath ());
                 QList<QFileInfo> fileLst = path.entryInfoList (QDir::AllEntries |
                                                                QDir::NoDotAndDotDot);
@@ -743,7 +743,7 @@
                 emit file_remove_signal (info.filePath (), QString ());
                 // Remove the file.
                 bool st = m_file_system_model->remove (index);
-                // reload the old file if removing was not successful
+                // Reload the old file if removing was not successful
                 if (! st)
                   emit file_renamed_signal (false);
               }
@@ -864,7 +864,7 @@
 
   void files_dock_widget::notice_settings (const gui_settings *settings)
   {
-    // Qsettings pointer is checked before emitting.
+    // QSettings pointer is checked before emitting.
 
     int size_idx = settings->value (global_icon_size).toInt ();
     size_idx = (size_idx > 0) - (size_idx < 0) + 1;  // Make valid index from 0 to 2

--- a/libgui/src/gui-preferences-mw.h	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/gui-preferences-mw.h	Thu Apr 11 07:37:20 2019 -0400
@@ -34,7 +34,7 @@
   0x00,0x00,0x00,0x00,0x00,0x00,0x05,0x00
 };
 
-// FIXME: usew the following version when Qt4 support is dropped
+// FIXME: use the following version when Qt4 support is dropped
 // QVariant (QByteArrayLiteral ("\x1\xd9\xd0\xcb\0\x2\0\0\0\0\0\0\0\0\0\x1b\0\0\x3\xaf\0\0\x2\xb8\0\0\0\0\0\0\0\x39\0\0\x3\xaf\0\0\x2\xb8\0\0\0\0\0\0\0\0\x5\0")));
 const gui_pref
 mw_geometry ("MainWindow/geometry",
@@ -77,7 +77,7 @@
   '\0',0xff,0xff,0xff,0xff,'\0','\0','\0','\0','\0','\0','\0','\0'
 };
 
-// FIXME: usew the following version when Qt4 support is dropped
+// FIXME: use the following version when Qt4 support is dropped
 // QVariant (QByteArrayLiteral ("\0\0\0\xff\0\0\0\0\xfd\0\0\0\x2\0\0\0\0\0\0\x1&\0\0\x2+\xfc\x2\0\0\0\x3\xfb\0\0\0\x1e\0\x46\0i\0l\0\x65\0s\0\x44\0o\0\x63\0k\0W\0i\0\x64\0g\0\x65\0t\x1\0\0\0?\0\0\0\xac\0\0\0\x88\0\xff\xff\xff\xfb\0\0\0\x1a\0W\0o\0r\0k\0s\0p\0\x61\0\x63\0\x65\0V\0i\0\x65\0w\x1\0\0\0\xf1\0\0\0\xca\0\0\0\x82\0\xff\xff\xff\xfb\0\0\0\"\0H\0i\0s\0t\0o\0r\0y\0\x44\0o\0\x63\0k\0W\0i\0\x64\0g\0\x65\0t\x1\0\0\x1\xc1\0\0\0\xa9\0\0\0\x82\0\xff\xff\xff\0\0\0\x1\0\0\x2\x84\0\0\x2+\xfc\x2\0\0\0\x1\xfc\0\0\0?\0\0\x2+\0\0\0\xeb\x1\0\0\x1b\xfa\0\0\0\0\x2\0\0\0\x4\xfb\0\0\0$\0T\0\x65\0r\0m\0i\0n\0\x61\0l\0\x44\0o\0\x63\0k\0W\0i\0\x64\0g\0\x65\0t\x1\0\0\0\0\xff\xff\xff\xff\0\0\0\x46\0\xff\xff\xff\xfb\0\0\0.\0\x44\0o\0\x63\0u\0m\0\x65\0n\0t\0\x61\0t\0i\0o\0n\0\x44\0o\0\x63\0k\0W\0i\0\x64\0g\0\x65\0t\x1\0\0\0\0\xff\xff\xff\xff\0\0\0\xcf\0\xff\xff\xff\xfb\0\0\0\x14\0\x46\0i\0l\0\x65\0\x45\0\x64\0i\0t\0o\0r\x1\0\0\0\0\xff\xff\xff\xff\0\0\0\x62\0\xff\xff\xff\xfb\0\0\0\x1c\0V\0\x61\0r\0i\0\x61\0\x62\0l\0\x65\0\x45\0\x64\0i\0t\0o\0r\x1\0\0\0\0\xff\xff\xff\xff\0\0\0;\0\xff\xff\xff\0\0\0\0\0\0\x2+\0\0\0\x4\0\0\0\x4\0\0\0\b\0\0\0\b\xfc\0\0\0\x1\0\0\0\x2\0\0\0\x1\0\0\0\x16\0M\0\x61\0i\0n\0T\0o\0o\0l\0\x42\0\x61\0r\x1\0\0\0\0\xff\xff\xff\xff\0\0\0\0\0\0\0\0")));
 const gui_pref
 mw_state ("MainWindow/windowState",

--- a/libgui/src/history-dock-widget.h	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/history-dock-widget.h	Thu Apr 11 07:37:20 2019 -0400
@@ -50,12 +50,12 @@
 
     void information (const QString& message);
 
-    //! Signal emitted, whenever the user double-clicked a command in the
+    //! Signal emitted whenever the user double-clicks a command in the
     //! history.
 
     void command_double_clicked (const QString& command);
 
-    //! Signale emitted, whenever the user selects commands and chooses
+    //! Signal emitted whenever the user selects commands and chooses
     //! "Create script" from the popup menu.
 
     void command_create_script (const QString& commands);

--- a/libgui/src/m-editor/file-editor-tab.cc	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/m-editor/file-editor-tab.cc	Thu Apr 11 07:37:20 2019 -0400
@@ -323,8 +323,9 @@
 
   void file_editor_tab::handle_context_menu_edit (const QString& word_at_cursor)
   {
-    // search for a subfunction in actual file (this is done at first because
-    // octave finds this function before other with same name in the search path
+    // Search for a subfunction in actual file (this is done first because
+    // Octave finds this function before others with the same name in the
+    // search path.
     QRegExp rxfun1 ("^[\t ]*function[^=]+=[\t ]*"
                     + word_at_cursor + "[\t ]*\\([^\\)]*\\)[\t ]*$");
     QRegExp rxfun2 ("^[\t ]*function[\t ]+"
@@ -366,7 +367,7 @@
 
   // If "dbstop if ..." selected from context menu, create a conditional
   // breakpoint.  The default condition is (a) the existing condition if there
-  // is already a breakpoint (b) any selected text, or (c) empty
+  // is already a breakpoint, (b) any selected text, or (c) empty
   void file_editor_tab::handle_context_menu_break_condition (int linenr)
   {
     // Ensure editor line numbers match Octave core's line numbers.
@@ -631,7 +632,7 @@
           }
         else if (! valid_file_name ())
           {
-            // new, no yet named file: let us assume it is octave
+            // new, not yet named file: let us assume it is octave
 #if defined (HAVE_LEXER_OCTAVE)
             lexer = new QsciLexerOctave ();
             m_is_octave_file = true;
@@ -662,7 +663,7 @@
           delete old_lexer;
         m_edit_area->setLexer (lexer);
 
-        // build information for auto completion (APIs)
+        // Build information for auto completion (APIs)
         m_lexer_apis = new QsciAPIs (lexer);
 
         connect (this, SIGNAL (request_add_octave_apis (const QStringList&)),
@@ -725,14 +726,14 @@
         if (m_is_octave_file)
           {
             // Keywords and Builtins do not change, these informations can be
-            // stored in prepared form in a file. Information on function are
-            // changing frequently, then if functions should also be auto-
-            // completed, the date of any existing file is checked.
+            // stored in prepared form in a file.  Informations on functions
+            // are changing frequently, then if functions should also be
+            // auto-completed, the date of any existing file is checked.
 
             // Keywords are always used
             m_prep_apis_file = m_prep_apis_path + lexer->lexer () + "_k";
 
-            // Buitlins are only used if the user settings say so
+            // Builtins are only used if the user settings say so
             if (octave_builtins)
               m_prep_apis_file += 'b';
 
@@ -887,7 +888,7 @@
     m_edit_area->set_selection_marker_color (hg);
 
     // fix line number width with respect to the font size of the lexer and
-    // set the line numbers font depending on the lexers font
+    // set the line numbers font depending on the lexer's font
     if (settings->value (ed_show_line_numbers).toBool ())
       {
         // Line numbers width
@@ -1773,7 +1774,7 @@
     // reset the possibly still existing read only state
     m_edit_area->setReadOnly (false);
 
-    // if we are in this slot and the list of breakpoint is not empty,
+    // if we are in this slot and the list of breakpoints is not empty,
     // then this tab was saved during an exit of the applications (not
     // restoring the breakpoints and not emptying the list) and the user
     // canceled this closing late on.
@@ -1972,7 +1973,7 @@
 
     int count_crlf = text.count (eol_crlf);
     int count_lf = text.count (eol_lf) - count_crlf;  // isolated lf
-    int count_cr = text.count (eol_cr) - count_crlf;  // isolated cr;
+    int count_cr = text.count (eol_cr) - count_crlf;  // isolated cr
 
     resource_manager& rmgr = m_octave_qobj.get_resource_manager ();
     gui_settings *settings = rmgr.get_settings ();
@@ -2283,7 +2284,7 @@
     // set the window title to actual filename (not modified)
     update_window_title (false);
 
-    // files is save -> not modified, update encoding in statusbar
+    // file is save -> not modified, update encoding in statusbar
     m_edit_area->setModified (false);
     m_enc_indicator->setText (m_encoding);
 
@@ -2534,7 +2535,7 @@
     if (file_exists && ! do_close)
       {
         // Test if file is really modified or if just the timezone has
-        // changed. In the latter, just return without doing anything
+        // changed.  In the latter, just return without doing anything.
         QDateTime modified = QFileInfo (m_file_name).lastModified ().toUTC ();
 
         if (modified <= m_last_modified)
@@ -2592,7 +2593,7 @@
           }
 
         // give editor and this tab the focus,
-        // possibly making the editor visible  if it is hidden
+        // possibly making the editor visible if it is hidden
         emit set_focus_editor_signal (this);
         m_edit_area->setFocus ();
 
@@ -2827,7 +2828,7 @@
       }
     else
       {
-        // do not reload: readd to the file watche
+        // do not reload: readd to the file watcher
         m_file_system_watcher.addPath (m_file_name);
       }
   }
@@ -2864,7 +2865,7 @@
 
         if (m_edit_area->isModified ())
           {
-            // The best that can be done if the editor contents has been
+            // The best that can be done if the editor contents have been
             // modified is to see if there is a match with the original
             // line number of any existing breakpoints.  We can put a normal
             // debugger pointer at that breakpoint position.  Otherwise, it
@@ -3083,9 +3084,9 @@
 
         // Here we go for breaking the current line by inserting a newline.
         // For determining the position of a specific column, we have to get
-        // the column from the QScintila function without taking tab lengths
-        // into account, since the calculation from line/col to position ignores
-        // this, too
+        // the column from the QScintilla function without taking tab lengths
+        // into account, since the calculation from line/col to position
+        // ignores this, too.
         m_edit_area->getCursorPosition (&line, &col);
         int c = 0;
         int col_space = col;

--- a/libgui/src/m-editor/file-editor-tab.h	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/m-editor/file-editor-tab.h	Thu Apr 11 07:37:20 2019 -0400
@@ -116,10 +116,9 @@
                                          bool remove_on_success,
                                          bool restore_breakpoints);
 
-    // FIXME: The following is similar to "process_octave_code"
-    // signal.  However, currently that signal is connected to
-    // something that simply focuses a window and not actually
-    // communicate with Octave.
+    // FIXME: The following is similar to "process_octave_code" signal.
+    // However, currently that signal is connected to something that simply
+    // focuses a window and does not actually communicate with Octave.
     //
     // void evaluate_octave_command (const QString& command);
 
@@ -217,7 +216,7 @@
     void handle_save_file_as_answer_cancel (void);
     void handle_save_as_filter_selected (const QString& filter);
 
-    // When user changes encoding after decoding errors where found
+    // When user changes encoding after decoding errors were found
     void handle_current_enc_changed (const QString& enc);
 
     // When apis preparation has finished and is ready to save

--- a/libgui/src/m-editor/file-editor.cc	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/m-editor/file-editor.cc	Thu Apr 11 07:37:20 2019 -0400
@@ -96,12 +96,12 @@
   file_editor::file_editor (QWidget *p, base_qobject& oct_qobj)
     : file_editor_interface (p, oct_qobj)
   {
-    // Set current editing directory before construct because loaded
+    // Set current editing directory before construction because loaded
     // files will change ced accordingly.
     m_ced = QDir::currentPath ();
 
-    // set action that are later added by the main window to null,
-    // preventing access to them when they are still undefined
+    // Set actions that are later added by the main window to null,
+    // preventing access to them when they are still undefined.
     m_undo_action = nullptr;
     m_copy_action = nullptr;
     m_paste_action = nullptr;
@@ -171,7 +171,7 @@
     QString sc_cont = settings->sc_value (sc_main_debug_continue);
 
     if (sc_run == sc_cont)
-      m_run_action->setShortcut (QKeySequence ());  // prevent ambigous shortcuts
+      m_run_action->setShortcut (QKeySequence ());  // prevent ambiguous shortcuts
 
     m_run_action->setToolTip (tr ("Continue"));   // update tool tip
   }
@@ -247,7 +247,7 @@
 
     if (startup && ! isFloating ())
       {
-        // check is editor is really visible or hidden between tabbed widgets
+        // check if editor is really visible or hidden between tabbed widgets
         QList<QTabBar *> tab_list = main_win ()->findChildren<QTabBar *>();
 
         bool in_tab = false;
@@ -323,7 +323,7 @@
 
     qSort (s_data);
 
-    // finally open the file with the desired encoding in the desired order
+    // finally open the files with the desired encoding in the desired order
     for (int n = 0; n < s_data.count (); ++n)
       request_open_file (s_data.at (n).file_name, s_data.at (n).encoding,
                          s_data.at (n).line);
@@ -391,13 +391,12 @@
 
   bool file_editor::check_closing (void)
   {
-    // When the application or the editor is closing and the user wants
-    // to close all files in the latter case all editor tabs are checked
-    // whether they need to be saved. During these ckecked the tabs are
-    // not closed since the user might cancel closing octave during one
-    // of these saving dialogs. Therefore, saving the session for
-    // restoring at next start is not done before the application is
-    // definitely closing.
+    // When the application or the editor is closing and the user wants to
+    // close all files, in the latter case all editor tabs are checked whether
+    // they need to be saved.  During these checks tabs are not closed since
+    // the user might cancel closing Octave during one of these saving dialogs.
+    // Therefore, saving the session for restoring at next start is not done
+    // before the application is definitely closing.
 
     std::list<file_editor_tab *> fe_tab_lst = m_tab_widget->tab_list ();
     m_number_of_tabs = fe_tab_lst.size ();
@@ -415,11 +414,10 @@
 
     for (auto fe_tab : fe_tab_lst)
       {
-        // If there was a cancellation, make the already saved/discarded
-        // tabs recovering from the exit by removing the read-only state
-        // and by recovering the debugger breakpoints. Finally return
-        // false in order to cancel closing the application or the
-        // editor
+        // If there was a cancellation, make the already saved/discarded tabs
+        // recover from the exit by removing the read-only state and by
+        // recovering the debugger breakpoints.  Finally return false in order
+        // to cancel closing the application or the editor.
 
         if (fe_tab->check_file_modified (false) == QMessageBox::Cancel)
           {
@@ -497,7 +495,7 @@
     // Finally close all the tabs and return indication that we can exit
     // the application or close the editor.
     // Closing and deleting the tabs makes the editor visible. In case it was
-    // hidden before, this state has to be restored afterwards
+    // hidden before, this state has to be restored afterwards.
     bool vis = isVisible ();
 
     for (auto editor_tab : editor_tab_lst)
@@ -997,7 +995,7 @@
       {
         // Note: to overwrite the contents of some other file editor tab
         // with the same name requires identifying which file editor tab
-        // that is (not too difficult) then close that tab.  Of course,
+        // that is (not too difficult) then closing that tab.  Of course,
         // that could trigger another dialog box if the file editor tab
         // with the same name has modifications in it.  This could become
         // somewhat confusing to the user.  For now, opt to do nothing.
@@ -1086,7 +1084,7 @@
     request_open_file (file);
   }
 
-  // Slot used for signals indicating that a file was changed/rename or
+  // Slot used for signals indicating that a file was changed/renamed or
   // is going to be deleted/renamed
   void file_editor::handle_file_remove (const QString& old_name,
                                         const QString& new_name)
@@ -1165,8 +1163,8 @@
   {
     m_no_focus = true;  // Remember for not focussing editor
 
-    // Loop over all file that have to be reloaded. Start at the end of the
-    // list, otherwise the stored indexes are not correct
+    // Loop over all files that have to be reloaded. Start at the end of the
+    // list, otherwise the stored indexes are not correct.
     for (int i = m_tmp_closed_files.count () - 1; i >= 0; i--)
       {
         // Load old or new file
@@ -1297,8 +1295,8 @@
 
   void file_editor::set_shortcuts (void)
   {
-    // Shortcuts also available in the main window, as well as the realted
-    // ahotcuts, are defined in main_window and added to the editor
+    // Shortcuts also available in the main window, as well as the related
+    // shortcuts, are defined in main_window and added to the editor
 
     shortcut_manager& scmgr = m_octave_qobj.get_shortcut_manager ();
 
@@ -1388,8 +1386,8 @@
   }
 
   // This slot is a reimplementation of the virtual slot in octave_dock_widget.
-  // We need this for creating an empty script when the editor has no open files
-  // and is made visible
+  // We need this for creating an empty script when the editor has no open
+  // files and is made visible.
   void file_editor::handle_visibility (bool visible)
   {
     if (m_closed && visible)
@@ -1473,8 +1471,8 @@
 
     if (openFileName.isEmpty ())
       {
-        // This happens if edit is calles without an argument
-        // Open eitor with empty edit area instead (as new file would do)
+        // This happens if edit is called without an argument
+        // Open editor with empty edit area instead (as new file would do)
         request_new_file ("");
       }
     else
@@ -1807,7 +1805,7 @@
     // FIXME: what was the intended purpose of this unused variable?
     // QStyle *editor_style = QApplication::style ();
 
-    // Menu bar: do not set it native, required in MacOS and Ubuntu Unity (Qt5)
+    // Menu bar: do not set it native, required in macOS and Ubuntu Unity (Qt5)
     // for a visible menu bar in the editor widget. This property is ignored
     // on other platforms.
     m_menu_bar = new QMenuBar (editor_widget);
@@ -2590,7 +2588,7 @@
         // 1. The path of the file rel. to the dir is not equal to the
         //    its absolute one.
         //    If both are equal, then there is no relative path and removed
-        //    directoy and file are on different drives (e.g.on windows)
+        //    directory and file are on different drives (e.g. on windows)
         // 2. The (real) relative path does not start with "../", i.e.,
         //    the file can be reached from the directory by descending only
         if ((rel_path_to_file != abs_path_to_file)

--- a/libgui/src/m-editor/find-dialog.cc	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/m-editor/find-dialog.cc	Thu Apr 11 07:37:20 2019 -0400
@@ -613,7 +613,7 @@
         _edit_area->getCursorPosition (&line,&col);
 
         _rep_all = 1;
-        find_next ();  // find first occurence (forward)
+        find_next ();  // find first occurrence (forward)
 
         _edit_area->beginUndoAction ();
         while (_find_result_available)   // while search string is found

--- a/libgui/src/m-editor/octave-qscintilla.cc	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/m-editor/octave-qscintilla.cc	Thu Apr 11 07:37:20 2019 -0400
@@ -609,7 +609,7 @@
       }
   }
 
-  // Do smart indendation of current selection or line.
+  // Do smart indentation of current selection or line.
   void octave_qscintilla::smart_indent_line_or_selected_text (int lineFrom,
                                                               int lineTo)
   {
@@ -1171,7 +1171,7 @@
   void octave_qscintilla::auto_close (int auto_endif, int linenr,
                                       const QString& line, QString& first_word)
   {
-    // Insert and "end" for an "if" etc., if needed.
+    // Insert an "end" for an "if" etc., if needed.
     // (Use of "while" allows "return" to skip the rest.
     // It may be clearer to use "if" and "goto",
     // but that violates the coding standards.)

--- a/libgui/src/main-window.cc	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/main-window.cc	Thu Apr 11 07:37:20 2019 -0400
@@ -228,7 +228,7 @@
 
     init_terminal_size ();
 
-    // Connect signals for changes in visibility not before window is
+    // Connect signals for changes in visibility now before window is
     // shown.
 
     connect_visibility_changed ();
@@ -311,7 +311,7 @@
   void main_window::focus_changed (QWidget *, QWidget *new_widget)
   {
     // If there is no new widget (e.g., when pressing <alt> and the global
-    // menu gets active, we can return immediately
+    // menu gets active), we can return immediately
     if (! new_widget)
       return;
 
@@ -325,7 +325,7 @@
     while (w_new && w_new != m_main_tool_bar && count < 100)
       {
         // Go through all dock widgets and check whether the current widget
-        // widget with focus is a child of one of it
+        // with focus is a child of one of them.
         for (auto w : w_list)
           {
             if (w->isAncestorOf (w_new))
@@ -335,7 +335,7 @@
         if (dock)
           break;
 
-        // If not yet found (in case w_new is not a childs of its dock widget),
+        // If not yet found (in case w_new is not a child of its dock widget),
         // test next widget in the focus chain
         w_new = qobject_cast<QWidget *> (w_new->previousInFocusChain ());
 
@@ -880,7 +880,7 @@
         QString name = widget->objectName ();
         if (! name.isEmpty ())
           {
-            // if children has a name
+            // if child has a name
             icon = dw_icon_set_names[icon_set_found].path; // prefix | octave-logo
             if (dw_icon_set_names[icon_set_found].name != "NONE")
               icon += name + ".png"; // add widget name and ext.
@@ -1041,7 +1041,7 @@
   void main_window::accept_directory_line_edit (void)
   {
     // Get new directory name, and change to it if it is new.  Otherwise,
-    // the combo box will triggers the "activated" signal to change to the
+    // the combo box will trigger the "activated" signal to change to the
     // directory.
 
     QString dir = m_current_directory_combo_box->currentText ();
@@ -1303,7 +1303,7 @@
 
     if (ok && new_name.length () > 0)
       {
-        // append suffix if it not already exists
+        // append suffix if it does not already exist
         if (new_name.rightRef (2) != ".m")
           new_name.append (".m");
         // check whether new files are created without prompt
@@ -1329,7 +1329,7 @@
        {
          // INTERPRETER THREAD
 
-         // Split possible subfuntions
+         // Split possible subfunctions
          QStringList fcn_list = fname.split ('>');
          QString fcn_name = fcn_list.at (0) + ".m";
 
@@ -1484,7 +1484,7 @@
   void main_window::set_window_layout (gui_settings *settings)
   {
     // Restore main window state and geometry from settings file or, in case
-    // of an error from the default layout
+    // of an error, from the default layout.
     if (settings)
       {
         if (! restoreState (settings->value (mw_state).toByteArray ()))
@@ -1567,7 +1567,7 @@
 
     settings->setValue (mw_geometry.key, saveGeometry ());
     settings->setValue (mw_state.key, saveState ());
-    // write the list of recent used directories
+    // write the list of recently used directories
     QStringList curr_dirs;
     for (int i=0; i<m_current_directory_combo_box->count (); i++)
       {
@@ -1776,7 +1776,7 @@
   {
     // this slot is called when the terminal gets/loses focus
 
-    // return if the user don't want to use readline shortcuts
+    // return if the user doesn't want to use readline shortcuts
     if (! m_prevent_readline_conflicts)
       return;
 
@@ -1884,7 +1884,7 @@
   }
 
   // The following slot is called after files have been selected in the
-  // open file dialog., possibly with a new selected encoding stored in
+  // open file dialog, possibly with a new selected encoding stored in
   // m_file_encoding
   void main_window::request_open_files (const QStringList& open_file_names)
   {
@@ -2145,7 +2145,7 @@
     connect (m_file_browser_window, SIGNAL (file_renamed_signal (bool)),
              m_editor_window, SLOT (handle_file_renamed (bool)));
 
-    // Signals for removing/renaming files/dirs in the temrinal window
+    // Signals for removing/renaming files/dirs in the terminal window
     connect (qt_link, SIGNAL (file_renamed_signal (bool)),
              m_editor_window, SLOT (handle_file_renamed (bool)));
 #endif
@@ -2475,7 +2475,7 @@
     clipboard_has_changed ();
 #if defined (Q_OS_WIN32)
     // Always enable paste action (unreliable clipboard signals in windows)
-    // FIXME: This has to be removed, when the clipboards signals in windows
+    // FIXME: This has to be removed, when the clipboard signals in windows
     //        are working again
     m_paste_action->setEnabled (true);
     m_clear_clipboard_action->setEnabled (true);
@@ -2539,7 +2539,7 @@
 
   void main_window::editor_tabs_changed (bool have_tabs)
   {
-    // Set state of action which depend on the existance of editor tabs
+    // Set state of actions which depend on the existence of editor tabs
     m_editor_has_tabs = have_tabs;
     m_debug_step_over->setEnabled (have_tabs);
   }
@@ -2559,7 +2559,7 @@
       {
         if (checkable)
           {
-            // action for visibilty of dock widget
+            // action for visibility of dock widget
             connect (action, SIGNAL (toggled (bool)),
                      widget, SLOT (setVisible (bool)));
 

--- a/libgui/src/octave-dock-widget.cc	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/octave-dock-widget.cc	Thu Apr 11 07:37:20 2019 -0400
@@ -173,8 +173,8 @@
                     "}\n"
                     ).arg (close_icon).arg (float_icon).arg (icon_size)
                      .arg (close_tooltip).arg (float_tooltip)
-                     .arg (titlebar_foreground). arg (titlebar_background)
-                     .arg ((icon_size*2)/3). arg((icon_size*7)/3);
+                     .arg (titlebar_foreground).arg (titlebar_background)
+                     .arg ((icon_size*2)/3).arg((icon_size*7)/3);
   }
 
   octave_dock_widget::octave_dock_widget (const QString& obj_name, QWidget *p,

--- a/libgui/src/octave-dock-widget.h	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/octave-dock-widget.h	Thu Apr 11 07:37:20 2019 -0400
@@ -96,7 +96,7 @@
   signals:
 
     //! Custom signal that tells whether a user has clicked away that dock
-    //! widget, i.e the active dock widget has changed.
+    //! widget, i.e. the active dock widget has changed.
 
     void active_changed (bool active);
 

--- a/libgui/src/resource-manager.cc	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/resource-manager.cc	Thu Apr 11 07:37:20 2019 -0400
@@ -92,7 +92,7 @@
         // location ($HOME/.config/octave/qt-settings) for impoting all
         // available keys into the new settings file.
         // Do not look for an old settings file if XDG_CONFIG_HOME is set,
-        // since then a non-existin new settings file does not necessarily
+        // since then a nonexistent new settings file does not necessarily
         // indicate a first run of octave with new config file locations.
 #if defined (HAVE_QSTANDARDPATHS)
         QString home_path
@@ -109,7 +109,7 @@
 
         if (ofile.exists ())
           {
-            // Old settings file exists, create a gui_settings object related
+            // Old settings file exists; create a gui_settings object related
             // to it and copy all available keys to the new settings
             gui_settings old_settings (old_settings_file, QSettings::IniFormat);
 
@@ -377,8 +377,8 @@
     if (! m_settings->value (global_icon_theme).toBool ())
       return QIcon (":/actions/icons/" + icon_name + ".png");
 
-    // Use system icon theme with own files as fallback except the fallback is
-    // explicitly disabled (fallback=false)
+    // Use system icon theme with own files as fallback except when the
+    // fallback is explicitly disabled (fallback=false)
     if (fallback)
       return QIcon::fromTheme (icon_name,
                                QIcon (":/actions/icons/" + icon_name + ".png"));

--- a/libgui/src/shortcut-manager.cc	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/shortcut-manager.cc	Thu Apr 11 07:37:20 2019 -0400
@@ -191,8 +191,8 @@
     init (tr ("Community News"), sc_main_news_community_news);
 
     // Tab handling
-    // The following shortcuts are moved into a separate tab. The key names
-    // are not change for preserving compatibility with older versions
+    // The following shortcuts are moved into a separate tab.  The key names
+    // are not changed, to preserve compatibility with older versions.
     init (tr ("Close Tab"), sc_edit_file_close);
     init (tr ("Close All Tabs"), sc_edit_file_close_all);
     init (tr ("Close Other Tabs"), sc_edit_file_close_other);
@@ -620,7 +620,7 @@
     shortcut_info.m_default_sc = settings->sc_def_value (sc);
     m_sc << shortcut_info;
 
-    // insert shortcut in order check for duplicates later
+    // insert shortcut in order to check for duplicates later
     if (! actual.isEmpty ())
       m_shortcut_hash[actual.toString ()] = m_sc.count ();
     m_action_hash[sc.key] = m_sc.count ();

--- a/libgui/src/tab-bar.cc	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/tab-bar.cc	Thu Apr 11 07:37:20 2019 -0400
@@ -21,7 +21,7 @@
 */
 
 // This file implements a tab bar derived from QTabBar with a contextmenu
-// and possibility to close a tab via double-left and middle mouse click.
+// and possibility to close a tab via double-left or middle mouse click.
 
 #if defined (HAVE_CONFIG_H)
 #  include "config.h"
@@ -182,8 +182,8 @@
                 // A tab was closed:
                 // Was the possibly only closed tab before or after the
                 // previously current tab? According to the result, use previous
-                // index or reduce it by one. Also prevent using a too large
-                // if other or all files were closed.
+                // index or reduce it by one.  Also prevent using a too large
+                // index if other or all files were closed.
                 int new_idx = count () - 1;
                 if (new_idx > 0)
                   {

--- a/libgui/src/tab-bar.h	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/tab-bar.h	Thu Apr 11 07:37:20 2019 -0400
@@ -21,7 +21,7 @@
 */
 
 // This file implements a tab bar derived from QTabBar with a contextmenu
-// and possibility to close a tab via double-left and middle mouse click.
+// and possibility to close a tab via double-left or middle mouse click.
 
 #if ! defined (octave_tab_bar_h)
 #define octave_tab_bar_h 1

--- a/libgui/src/variable-editor.cc	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/variable-editor.cc	Thu Apr 11 07:37:20 2019 -0400
@@ -1291,7 +1291,7 @@
 
     // Must supply a title for a QLabel to be created.  Calling set_title()
     // more than once will add more QLabels.  Could change octave_dock_widget
-    // to always supply a QLabl (initially empty) and then simply update its
+    // to always supply a QLabel (initially empty) and then simply update its
     // contents.
     page->set_title (name);
     if (page->titleBarWidget () != nullptr)
@@ -1660,7 +1660,7 @@
     action->setStatusTip(tr("Go one level up in variable hierarchy"));
 
     // The QToolButton mouse-clicks change active window, so connect all
-    // HoverToolButton and RuternFocusToolButton objects to the mechanism
+    // HoverToolButton and ReturnFocusToolButton objects to the mechanism
     // that restores active window and focus before acting.
     QList<HoverToolButton *> hbuttonlist
       = m_tool_bar->findChildren<HoverToolButton *> (""

--- a/libgui/src/variable-editor.h	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/variable-editor.h	Thu Apr 11 07:37:20 2019 -0400
@@ -220,9 +220,8 @@
     variable_editor_model *m_var_model;
   };
 
-  // Gadgets to keep track and restore what variable window
-  // was in focus just prior to selecting something on the
-  // menu bar
+  // Gadgets to keep track of and restore what variable window was in focus
+  // just prior to selecting something on the menu bar.
 
   class HoverToolButton : public QToolButton
   {

--- a/libgui/src/workspace-model.cc	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/workspace-model.cc	Thu Apr 11 07:37:20 2019 -0400
@@ -48,7 +48,7 @@
     m_columnNames.append (tr ("Value"));
     m_columnNames.append (tr ("Attribute"));
 
-    // Initialize the bachground and foreground colors of special
+    // Initialize the background and foreground colors of special
     // classes in the workspace view. The structure is
     // m_storage_class_colors(1,2,...,colors):        background colors
     // m_storage_class_colors(colors+1,...,2*colors): foreground colors
@@ -109,7 +109,7 @@
               = ws_class_chars.indexOf (m_scopes[idx.row ()].toLatin1 ());
             if (actual_class >= 0)
               {
-                // Valid class: Get backgorund (normal indexes) or foreground
+                // Valid class: Get background (normal indexes) or foreground
                 // color (indexes with offset)
                 if (role == Qt::ForegroundRole)
                   actual_class += ws_colors_count;

--- a/libgui/src/workspace-view.cc	Wed Jan 01 17:40:49 2020 +0100
+++ b/libgui/src/workspace-view.cc	Thu Apr 11 07:37:20 2019 -0400
@@ -180,7 +180,7 @@
 
     m_view->setModel (&m_filter_model);
 
-    // set the sorting after a model was set, it would be ignored otherwise
+    // set the sorting after the model is set, it would be ignored otherwise
     resource_manager& rmgr = m_octave_qobj.get_resource_manager ();
     gui_settings *settings = rmgr.get_settings ();
     m_view->sortByColumn (
@@ -333,7 +333,7 @@
 
     QModelIndex index = m_view->indexAt (qpos);
 
-    // if it isnt Local, Glocal etc, allow the ctx menu
+    // if it isn't Local, Global etc, allow the ctx menu
     if (index.isValid () && index.column () == 0)
       {
         QString var_name = get_var_name (index);