Initial proposal:
https://github.com/openjdk/jdk/pull/1496
==============================================
Looks like extended key codes set was filled with synonyms
https://wiki.linuxquestions.org/wiki/List_of_Keysyms_Recognised_by_Xmodmap
0x10006cc is a Farsi_yeh and also deprecated synonym Arabic_farsi_yeh
0x1000589 is an Armenian_full_stop and also deprecated synonym Armenian_verjaket
0x100055d is an Armenian_separation_mark and also deprecated synonym Armenian_but
0x100055b is an Armenian_accent and also deprecated synonym Armenian_shesht
0x100055e is an Armenian_question and also deprecated synonym Armenian_paruyk

Found by IntelliJ IDEA inspection Java | Probable bugs | Overwritten Map key or Set element