Hi All,
Really sorry about the late reply here,
we apologize for all the inconvenience caused by this issue. As Eric mentioned previously, we are having troubles to reproduce this issue in our test environment, however,
considering there are more and more users report the same issue in this thread, we would like to make a short summary to help the other infected users
to identify the issue quickly.
Issue Symptom:
-----------------------
When editing the pages in SharePoint Online, after click on
Edit, the Republish button will be missing on the pages.

Republish is missing in the following
image:

Also per
TrippMD &
mlewis' discussion, this issue won't appear on the newly created pages, but if you refresh
the new pages after the first publish, this issue will reoccur.
Recommendation:
-----------------------
Currently, we are trying to involve more related resources on this issue, unfortunately, we only have limited resources to report this
issue, if you are encountering with the same/similar issue in your tenant, please raise a support ticket as
webbrewers3 &
malikfarhan mentioned. This will draw more attention from the SharePoint Dev Team and
speed up the fixing procedure.
If there is any updates on this issue on your side, please come back and post here, we will keep monitoring on this thread.
Much appreciate for your patience and effort.
Regards,
Alex Chen