When I add tags to a question, the excerpt shown is the tag's excerpt. However, when a tag is a synonym of another one, this can be frustrating.
Can it show the excerpt of the synonym instead of its own excerpt?
The main reason for this is that we cannot edit the excerpt at all of that tag as there's no way to navigate to its page. Trying to navigate to that tag will always redirect to the main synonym.
Also, if the main synonym is a "banned" tag the ban message becomes very confusing. It will mention the main synonym in the message instead of the chosen tag.
Keep in mind that when you hover on a synonymized tag elsewhere, at least in the main synonym's page, it behaves in the desired way mentioned in this question. The excerpt shown is not its own, but it is the main synonym's excerpt.
The following is how the excerpts look in the tags field:
The following is the text that shows up if I hover over the tag on the synonym page.
The following is what shows as the ban message when I use the