Bug 479523

Summary:	Ctrl+Shift+U conflicts with fcitx5/ibus
Product:	[Applications] kate	Reporter:	spamless.9v5xj
Component:	general	Assignee:	KWrite Developers <kwrite-bugs-null>
Status:	CONFIRMED ---
Severity:	normal	CC:	nate
Priority:	NOR	Keywords:	usability
Version First Reported In:	24.01.85
Target Milestone:	---
Platform:	Neon
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description spamless.9v5xj 2024-01-08 01:18:58 UTC

The default keyboard shortcut to convert a highlighted string to lowercase, Ctrl+Shift+U, cannot be activated if one uses the fcitx or ibus IMEs, which map it to input Unicode by code point and take priority over Kate.

As far as I can tell fcitx does not provide a method to disable nor change this keyboard shortcut, with the only solution/workaround to temporarily disable the IME or to change the key combo in Kate.

STEPS TO REPRODUCE
1. Install fcitx5 with package manager of choice
2. Activate fcitx by opening System Settings > Input Devices > Virtual keyboard and selecting Fcitx5
3. Open Kate and select "New File"
4. Type in a string, eg. ABCDEF
5. Highlight the string
6. Press Ctrl+Shift+U

OBSERVED RESULT
  The string gets deleted and replaced with fcitx's Unicode code point input prompt

EXPECTED RESULT
  Honestly, not sure. Some sort of warning there's a keyboard shortcut conflict?

OTHER NOTES
  Issue also occurs on Plasma 5 running Kate version 23.08.4.

  I happen to know what component(s) cause this, but I can see this being extra confusing for some as the prompt consisting of a single uppercase U isn't particularly self-evident what it is.
  Please see https://superuser.com/questions/358749/how-to-disable-ctrlshiftu

  This might be better off being filed as a new bug, but there doesn't seem to be an option to toggle/cycle between lowercase, ALL CAPS and Camel Case which would save some shortcut keys.