Compare the behavior of the dropdown of the top search bar in Phabricator with e.g. the search box in the MediaWiki Vector skin [i.e. as in Wikipedia]. There, if you get several interesting search results in the dropdown, you can just middle-click them all to open them in new tabs (or right-click and select "Open in new window", or do any of the other things one can do with a link). Phabricator just navigates away in the current tab on any kind of click.

In https://phabricator.wikimedia.org/T76812#821076 @tgr wrote:

For MediaWiki that was T19808 / https://gerrit.wikimedia.org/r/#/c/23674/ ; in general, you need to make sure, that the search dropdown items are wrapped in <a> tags pointing to the right location, and that the click handler does not catch non-left-clicks or left clicks with a modifier key. The code we used in MediaViewer for that is

if ( e.altKey || e.shiftKey || e.ctrlKey || e.metaKey || e.button ) { /* let the browser handle the click * / }

although it will be a bit more tricky if you want to be handle old IE versions correctly.

Original report: https://phabricator.wikimedia.org/T76812