I can't load the project anymore. Took dumps (attached) and they indicate crash here with Integer Divide by Zero:

TextEditor.dll!TextEditor::Internal::TextEditorWidgetPrivate::updateLineAnnotation(const TextEditor::Internal::PaintEventData & data, const TextEditor::Internal::PaintEventBlockData & blockData, QPainter & painter) Line 5163
    at C:\Users\qt\work\build\qt-creator\src\plugins\texteditor\texteditor.cpp(5163)

Disabling clangd did not help, not wiping the build directory.

Creating a new session and loading that worked.

Seems I have accidentally zoomed out to 10% or less zoom as my wheel was scrolling.