Regarding the notification messages that appear at the top of the screen. For example, when entries are saved.

status and alert to announce this text to screen readers. (Related: #7139)A related point which may be interesting for you to hear.
One of the ways in which I work with Craft CMS, is that for multiple editing I may open many edit tabs for different entries at a time - sometimes 10 or 15 or more tabs.
Depending on which environment I am working on, the response time for saving an entry might take some time. Because of this, I may edit an entry, hit cmd + s to save, and switch to the next tab to edit that one, and repeat that flow.
A problem with the timer on the "_Entry saved_" notification is that when I go back to another tab, because it was displayed with a timer and has already been displayed, there's no clear indication as to whether I saved it or not (unless I check the timestamp, and even that may not be obvious enough). So quite often I end up saving again, just to be sure.
It's no biggie, but this particular use case occurs so frequently so it can be a bit annoying not knowing if I recently saved or not. A solution to the accessibility issues may help this use case too.
Or perhaps it just needs to make sure the user has the browser tab active before notifications such as these are displayed.
Good point! I think we can use the page visibility API to ensure that the time is paused while the tab isn't being viewed.
Related: #7572
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A related point which may be interesting for you to hear.
One of the ways in which I work with Craft CMS, is that for multiple editing I may open many edit tabs for different entries at a time - sometimes 10 or 15 or more tabs.
Depending on which environment I am working on, the response time for saving an entry might take some time. Because of this, I may edit an entry, hit
cmd + sto save, and switch to the next tab to edit that one, and repeat that flow.A problem with the timer on the "_Entry saved_" notification is that when I go back to another tab, because it was displayed with a timer and has already been displayed, there's no clear indication as to whether I saved it or not (unless I check the timestamp, and even that may not be obvious enough). So quite often I end up saving again, just to be sure.
It's no biggie, but this particular use case occurs so frequently so it can be a bit annoying not knowing if I recently saved or not. A solution to the accessibility issues may help this use case too.
Or perhaps it just needs to make sure the user has the browser tab active before notifications such as these are displayed.