at this point I think that this issue is becoming a more general one than that; I guess (can't test right now) that you would have the same issue
- even if your mountpoint is at another level different from 1
- and I think that it is even possible that it comes up even without workspaces at all, if your user or usergroup has a mountpoint and you try to create a page in parallel to that mountpoint (I repeat, I can't test right now, I'm just guessing)
I don't know if it would be possible to disallow every case...
Maybe it would be better to show a warning? "You are trying to create a page, but based on your current configuration, you won't be able to see it"; I don't know.
[UPDATE]¶
so far, I have performed the following tests with TYPO3 9.5.2-dev (latest master)
test 1 (done with admin user)¶
1) create a workspace and set the homepage as mount point
2) switch to workspace
3) right-click on homepage > create new page
4) save the new page
Result
problem #1 the page is actually created, but not visible
problem #2 it throws an error:
(1/1) #1534710048 TYPO3\CMS\Core\Exception\SiteNotFoundException
No pseudo-site found in root line of page 889
Problem #3 the new page is visible even on LIVE workspace (and it should not be)
Problem #4 it is not possible to delete the page via the context menu of the pagetree (but other means of deleting it, like the list view, work)
Test 2 (done with non-admin user)¶
1) Use a non-admin user with a mount point
2) right-click on the mount point page > create new page
Result: it is not possible to create the page
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No page new permission for user 2 on page 1437745640
Are there other tests/scenarios that comes in your mind?
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