Decided to speelchuck a Pluma plain text document and it kept highlighting words like didn't, couldn't, wouldn't and so-on, even though the word was listed in the replacement choices, so I told it to 'replace' out of sheer devilment (possibly).

So, it replaced didn't with didn't't and couldn't with couldn't't and wouldn't with wouldn't't.

Is this a 'feature' of Pluma, or has my installation got its knickers in a twist?

I might just remove Pluma and substitute Gedit...