Selecting a plugin alias (tiki-admin.php?page=textarea) and clicking "delete" gives a error (blank page) and nothing happen.
I've had this issue with different tiki versions:
9.4 (production website, using tiki since 2005)
9.4 (test website, fresh install)
9.6 (test website, updated from a 9.4 fresh install)
I could no reproduce it on tiki 9.4 on show.t.o, but I just tried a 9.3 instance, and I get the issue back with the following error message:
Fatal error: Call to undefined method ParserLib::set_preference() in /var/www/pianoliv-11386-4715/lib/parser/parserlib.php on line 701