(still me, replying from my .world account because I can't see your comment with my .blahaj)
I actually did try this, twice. First I mentioned something about it when we were still doing the "intro bit" (exchanging the contextual elements), but she skipped over it. Pretty much just like she did in high-school, honestly.
Then I tried doing an inside joke in reference to a relatively intimate moment, but that one may have been a bit too subtle on my part, so irrelevant.
I'm doing my best to just be open and honest. All I know right in the here and now is that I'm genuinely happy to be chatting with her again and that I'm feeling hints of starting to develop something more again. I'm not opposing or encouraging it, I'm doing baby steps and seeing where things go.
This is why I didn't and still don't want to bring it up.