Find and replace dialog should not be modal
A few issues with a modal dialog:
If one wishes to undo a replace operation they must close the dialog, undo, then reopen it.
If the user has the cursor in an undesirable position for starting a search, they must close the dialog, correct it, then reopen.
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Chad Schouggins commented
The find window is a rare sore spot of an otherwise lovely application. The modality of course being the biggest problem.
I'll second Magnus' suggestion that any NP++ inspiration would be welcome (eg, transparency on lose focus).
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Magnus Mikkelsen commented
Also if you need to copy one string to find, and another to replace with, you need to either open/close the dialog or type one of them in.
This could be avoided with a non-modal dialog.
I quite like the Find/replace dialog in notepad++ so didn't mind if you were inspired by it.