fix: high CPU load and unresponsiveness through SynEdit highlighter when starting to edit large text in popup editor

ansgarbecker · ansgarbecker · commit 676fcd793f5e · 2026-02-22T16:29:43.000+01:00
Refs #2388
diff --git a/extra/locale/heidisql.po b/extra/locale/heidisql.po
@@ -7,7 +7,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: HeidiSQL\n"
 "POT-Creation-Date: 2012-11-05 21:40\n"
-"PO-Revision-Date: 2026-02-19 18:41+0100\n"
+"PO-Revision-Date: 2026-02-22 16:29+0100\n"
 "Last-Translator: Ansgar Becker <anse@heidisql.com>\n"
 "Language-Team: English (http://www.transifex.com/projects/p/heidisql/language/en/)\n"
 "Language: en\n"
@@ -6648,8 +6648,8 @@ msgstr "Style:"
 msgid "Error in code formatting: %s"
 msgstr "Error in code formatting: %s"
 
-msgid "Auto-disabling wordwrap for large text"
-msgstr "Auto-disabling wordwrap for large text"
+msgid "Auto-disabling wordwrap and syntax highlighter for large text"
+msgstr "Auto-disabling wordwrap and syntax highlighter for large text"
 
 msgid "%d tab(s) took longer than expected to restore. Closing and reopening these should fix that: %s"
 msgstr "%d tab(s) took longer than expected to restore. Closing and reopening these should fix that: %s"
diff --git a/source/grideditlinks.pas b/source/grideditlinks.pas
@@ -1224,7 +1224,7 @@ function TInplaceEditorLink.BeginEdit: Boolean;
   if Result then begin
     FButton.Visible := ButtonVisible;
     SetBounds(Rect(0, 0, 0, 0));
-    if (Length(FEdit.Text) > SIZE_KB) or (ScanLineBreaks(FEdit.Text) <> lbsNone) then
+    if (Length(FEdit.Text) >= GRIDMAXDATA) or (ScanLineBreaks(FEdit.Text) <> lbsNone) then
       ButtonClick(FTree)
     else begin
       FPanel.Show;
diff --git a/source/texteditor.pas b/source/texteditor.pas
@@ -141,11 +141,15 @@ procedure TfrmTextEditor.SetText(text: String);
   end;
   if Assigned(Detected) then
     SelectLineBreaks(Detected);
-  if (Length(text) > SIZE_MB) then begin
-    MainForm.LogSQL(_('Auto-disabling wordwrap for large text'));
+  if (Length(text) > SIZE_KB*10) then begin
+    MainForm.LogSQL(_('Auto-disabling wordwrap and syntax highlighter for large text'));
     btnWrap.Enabled := False;
+    comboHighlighter.Enabled := False;
+    btnCustomizeHighlighter.Enabled := False;
   end else begin
     btnWrap.Enabled := True;
+    comboHighlighter.Enabled := True;
+    btnCustomizeHighlighter.Enabled := True;
   end;
 
   MemoText.Text := text;
@@ -379,6 +383,8 @@ procedure TfrmTextEditor.comboHighlighterSelect(Sender: TObject);
   SelStart, SelLength: Integer;
 begin
   // Code highlighter selected
+  if not comboHighlighter.Enabled then
+    Exit;
   SelStart := MemoText.SelStart;
   SelLength := MemoText.SelEnd - MemoText.SelStart;
   MemoText.Highlighter := nil;
