This lasts for maybe half an hour.
If I log out and log in, it’s still the same.
If I close Chrome and clean the cache with CCleaner, it’s still the same.
But I expect to get them all when I click on this button, from an observation showing the tag:
If I put the flag on this observation, it’s because I want to include this observation in this search.
(Moreover, in the present case, the “Casual” observation is from a botanical garden, so it makes sense, it may help to confirm the identification of the other “Wild” ones, by comparing them).
So I confirm my request, reformulated: the click on the tag button is expected to list all observations with this tag. (Otherwise we need too many manual actions to get the expected result).