issue13052.patch against 3.3a0 fixes the replace dialog. It also stops "Replace All" from closing the dialog. (What other application actually does this?)

When 'Regular Expression' is not checked, the find and the replace dialogs treat the fields as raw strings. This is consistent with Terry's description of "Normal".

When checked, the find field is treated as a RE and the replace field has "expand" applied.

I think this behavior is a good compromise as it allows for the basic effect of "Extended" when 'Regular Expression' is checked.

Also, I can not reproduce the beeping issue as being exclusive to '\'. I know it's caused by "text.bell()", but the bell occurs at appropriate times based on where it's located in the code (i.e. no more search results, find-again returns previous match, etc).