For about wikipedia.org/wiki/Facebook_Safety_Check working through the question https://webapps.stackexchange.com/questions/103217/will-facebook-safety-check-work-if-my-account-is-stuck-at-a-checkpoint-page, here is the research timeline:
Linearly blog-style going from the end to the beginning, (3) I asked about the "fact of if a user [currently stuck on checkpoint] still gets safety notifications" on https://ai.meta.stackexchange.com/questions/1495/is-fb-coms-safety-check-crisis-response-for-ai-stack-or-webapp-stack-if-zuc after (2) "boat programming" with https://ai.stackexchange.com/questions/10539/should-facebooks-safety-check-a-i-work-if-an-account-is-stuck-at-a-name-change led me to relearn the the scope of the original question at (1) https://webapps.stackexchange.com/questions/103217/will-facebook-safety-check-work-if-my-account-is-stuck-at-a-checkpoint-page originally showing how I did not realize I should have just said "Safety Check/Crisis Response Notification".
The final word from that experience, is how I did not focus on the main feature/ability of the Safety Check/Crisis Response being about the fact of a "Notification", which then if I may ask again, gives here final scope.
Quoting @AndrewT. from https://ai.meta.stackexchange.com/a/1497/22253:
"After the back-and-forth comments on this meta question and the revision to it, looks like the real question is
'I asked about the fact of if a user [currently stuck on checkpoint] still gets safety notifications.'
This is a clear question about the current policy of Facebook. While this is off-topic on AI.SE, this looks like on-topic on WebApps.SE based on their meta discussion: Are questions regarding website policies on-topic?
"I asked about the fact of if a user [currently stuck on checkpoint] still gets safety notifications."
"Will Facebook Safety Check work if my account is stuck at a Checkpoint page?"
= Will Facebook Safety Check / Crisis Response Notifications work if a user is stuck at a Checkpoint page? OR If a user is stuck at a Facebook Checkpoint will they still get Facebook Safety Check / Crisis Response Notifications?