Since 4.2.5 holding ctrl haven't has any effect on outline tool. Previously holding Ctrl would switch outline selection tool to polygon selection mode but no more.

1. Open 4.2.5.
2. Select outline selection tool.
3. Hold ctrl and click several times.
4. Nothing happens.

Expected result: The outline selection tool would switch to the polygon mode and would produce polygon selection.

This bug has been introduced in 4.2.5(Any platform: windows and linux tested, results are the same). In any previous version ctrl works fine. 

This bug is kinda duplicate of the bug: https://bugs.kde.org/show_bug.cgi?id=410532 but since the buttons in question there were alt and shift I've decided to make a separate bug report for ctrl key.

Also kinda unrelated there is no way to change this key in preferences to any other key modificator and there are no mentions of this functionality in Manual on docs.krita.org on the outline selection tools as well which is kinda confusing when you know that the feature exists but cannot find a trace of it in the docs(the page is only referencing to selection modifiers like add/substract/replace instead on modes of the selection itself).