id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
4167	[0.91-bugfixes][patch] FormFields have list-mutability issues with validator_list argument	Tom Tobin <korpios@…	James Bennett	In `0.91-bugfixes`, `FormFields` have list-mutability issues with the `validator_list` argument in their `__init__` methods; since `validator_list` has a default of `[]`, that very same list is mutated and re-used in future calls with a default value for `validator_list`.  By setting the default value to `None` and replacing `None` with `[]` in the method body, we avoid this issue.		closed	Core (Other)	0.91		fixed			Unreviewed	1	0	0	0	0	0