I had just tried and /ignore -r cleared all the nicks/hosts from the ignore list, how did you add an new ignore into the list, also some screenshots or a video will also help to see more clear your problem.
There have been no changes to the /ignore feature since v7.43 (and in fact quite a few versions before that). You may need to test this in a clean install to see if you can reproduce it and then try to narrow down the cause in your existing installation.