Currently, there is a bug in notepad++'s add extension feature only for Korean input after it was changed to hooking-based in the commit below.
b5a5baf#diff-eeb5624a35a43795da4eb970149a9ce7d22858b678a242affd2357520ea3e9f2R607
Bug
Attempting to save via Enter appends the last character to the extension.
Candidate mode is similar, with more varied issues depending on IME.
Cause
the hooking function is executed before the Hangul composition is completed and the last character is added after the extension.
Same for Candidate mode.
Workaround
It is almost impossible to fix issue 2 while maintaining the current Enter hooking
Exiting Candidate Mode can be done by pressing Enter, ESC, number key, or clicking on a candidate character, but there is too much code to cover all of these cases.
In addition, the Windows input framework is fragmented into IMM and TSF, and various IMEs have different implementations, so it is almost impossible to determine the state of Candidate or Hangul composition through IME hooking.
I have seen differences in the events fired by different Windows versions and different IME programs for the same IME behavior.
This PR solves problem 1 and partially solves problem 2 by not saving with Enter when in Hangul mode.
Fix#11582, fix#12225, fix#12366, close#13788
6330a688b1