For example, say you have https://example.org/long/path open in a background tab already, and you want to open the same URI in your current tab, so you start typing example.org into the address bar. Autocomplete shows you https://example.org/long/path [Switch to Tab], so you scroll down and select it so you don't need to type the entire address with the long path into the address bar.
Now the address bar says [Switch to Tab:] https://example.org/long/path, but you want to instead open the site in your current tab, and not switch to the already open tab. Clicking on the [Switch to Tab] icon in the address bar does nothing and doesn't get rid of it.
Visually, the only option is to either hit enter, and thus switch to the already open tab, or change the address in some way that autocomplete doesn't recognize it as the address of an already open tab. The solution I found to this issue is to start typing in the address bar, which changes the address slightly, then delete the changes and it removes the [Switch to Tab:] badge, allowing you to just hit enter and open the address in your current tab.
I don't think that behavior is intuitive or accessible. I think simply putting an exit icon like an x on the badge to be a good visual solution, like [x Switch to Tab:] https://example.org/long/path. Also, hitting the Esc key on your keyboard should also get rid of the [Switch to Tab:] badge from the address bar when you don't watch to switch to the tab.
I attached a screenshot as an example.