When there are two keywords assigned to a photo that have the same name but different case, e.g. Activity > march and Months > March, the keywording panel fails to fully qualify the keywords, showing "march, March" instead of "march < Activity, March < Months":
Further, if you type "March" in the keywording panel, you'll get an incorrect list of auto-complete suggestions "march" and "March", rather than "march < Activity" and "March < Months":
If you type "March" and hit enter, you'll incorrectly get "march < Acitivity".
If you type "March" and use the mouse to select the suggestion "March", you'll incorrectly get "march < Activity".
In general, LR aggressively ignores case of keywords everywhere except here. Looks like a programmer forgot to do a case-insensitive comparison.