Where is the definition for "preview"?

Question

We use the tilde a lot in one project, where the punctuation is close to French.

I know that when toggling to preview, all tildes will go away and show the non-breaking spaces.

Now we are using another similar placeholder § to have normal spaces in certain specific locations (where PT would kill them with its brutal auto-delete-spaces “feature”).

I know where to edit PrintDraftChanges.txt so that all is well in PDF output.

Now where please do I tell PT how to consider our § for the preview and turn them into regular spaces?

If there is another way, to just type spaces right after a \marker and protect it from PT, then that would be a better solution even.

Or if you happen to know a Unicode character that is included in “our normal fonts” and does look like a space but is not deleted by PT, that would be a nice hack too. It will need to behave like a breaking space, because it is typically followed by entire words, not just punctuation.

(For those who like to know context: We have a marker-pair for our glossary, where we can include [Greek] or [Hebrew] or [French] hints or origins of glossary entries. Like you see in dictionaries. Those are of course tagged as nonvernacular and so they throw our punctuation checking. This is why we would like the needed spaces inside our marker-pair and that in turn would put a space right after the opening marker, where PT keeps deleting it.)

Answer 1

Maybe I have just found an answer, minutes after posting:

I can include our new placeholder § in Language settings “word breaking characters”. That would enable the correct behaviour when toggling preview.

But: It would no longer be rendered as a space, but rather as a “nothing”. Then I noticed a hint about hyphens in the lateral Guide:

Immediately following the character in the box, enter (00AD) - include the parentheses - if you want a hyphen to appear when a long line wraps.

So my brain goes: “What if I place (0020) instead of (00AD)? Will it break PT?” Of course I had to try it and it seems to do what I want.

And a note to those who like to tweak things just right: Having changed the language settings like this, I lost a lot of my checking inventories (of course) because PT now has a new structure to work from. This did nothing ugly in our texts, but I will have to do plenty clicking and confirming in all the checking-inventories concerned. A small price for fruitful reasearch.