Hi -
I see that this was previously reported in the following thread:
https://discourse.mcneel.com/t/text-block-seems-to-have-changed-since-last-update-need-to-do-extra-click-into-the-box-first-to-write-text-how-to-i-stop-it-doing-this/
Can you run the Rhino SystemInfo command and copy-paste the result here? Also, do you know which version you were running before this one?
-wim