In "text comparison options" select to ignore nothing.
Click (or select in some way) "use ignores": it activates.
Then there is no way to deactivate it until you select something to ignore.
Nothing terrible, but I would expect the exact opposit.
When no Ignores are set in Text Comparison options and the ignores are disabled (button "use ignores" is not pressed), the button "use ignores" in the toolbar stays as is, i.e. not pressed and enabled.
If you press it, it becomes disabled and... pressed!
As I wrote, not a real problem since selecting any of the "ignores" reactivate il.
It's just an "estetical" note.