LR issues since Nov 2020 updated

[#1]

When i hit 'B' to add to a quick collection, i keep getting the following message
'Internal error has occurred : ?:0 attempt to compare string with nil'
Anyone got any idea what this is about?

[#2]

Plenty of people are having this problem. Search the forums for possible solutions.

[#3]

Your other option is to revert to LrC 9.4 until this gets straightened out.