Both editing inline and with WYSIWYG, steps and results:
user A edits the page and keeps the page opened
user B edits the same page and gets the message
Editing can be forced, but be aware of the warnings below. This page is currently locked by AdministratorAdministrator.
then if user B closes the page, but after some while tries again to open the same page, while the user A never closed his editing session, then indeed user B no longer receives the warning (that user A is still editing) -> so while A still edits the page, if B edits and closes, only the first time is warned
if the third user C tries the first time to open the page while A and B are still editing, then C first gets the warning that user B is editing the page
but if user C tries to edit the page the second time, while A and B are still editing, then starting with the second time user C no longer gets the warning
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