Disallowing line breaks before periods?

[ASC-Bre]

I am working in a document where I want to allow line breaks after certain characters (> / \ ). The issue I'm running into is that I now have certain cases where the line will break before a period, so that the period is now at the start of the next line.

Is there any way to allow automatic line breaks for certain characters but disallow breaks before periods?

[frameexpert]

There is this option under Format > Document > Text Options. If this doesn't solve your problem, please post a screenshot that shows some examples. Thank you.

[ASC-Bre]

That's for allowing line breaks after, and what I have already set. The problem is if I have a period after one of those marks, the period ends up at the beginning of the line, so I need to allow breaks after some marks but disallow before periods.

[Bob_Niland]

FM has a non-breaking hyphen (␛-h), for the hyphen case.

Another thing that would work is to convert troublesome instances of 
/ - – —
to visual mimics that would not be recognized by the Text Options settings. These could be Unicode characters, such as other dash forms with Stretch applied as needed.

A couple of things that don't work include:
☒ Replacing instances of —. with a Variable that is both characters. FM's rendering engine will split them anyway.
☒ Inserting a ZWJ character (U+200D ZERO WIDTH JOINER) between the — and . FM lets you do it, but doesn't honor the semantics of the ZWJ.