AFAICT, there's no way for a menu link plugin to cause the menu link not to appear.
There is MenuLinkInterface::isEnabled(), but returning FALSE from that causes the menu link itself to become disabled.
I've also tried returning either '' or NULL from getRouteName(), but that causes a routing crash. There's route '<none>' but that creates a link to the current page.
At this point the only thing I can see to do is to create a custom route which always denies access, and return that route name.
Use case is that I am writing a custom menu link plugin to show a user's group. If the user has no group memberships, then the link should not show.
Needs work
11.0 🔥
menu system
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It's likely this issue predates Contrib.social: some issue and comment data are missing.
acbramley → changed the visibility of the branch 2719609-menu-link-disabled to hidden.
Triaged as part of BSI.
Based on the code in MenuLinkTree::buildItems it looks like this bug could still exist in 11.x.
We need an IS update and a reroll onto an MR