I also have the same issue. Mine disappeared after editing an existing link to use tokens.
I have a user account menu. I added a link I want to use tokens in. When I enable the menu tokens checkbox, then add my link title and URL and save the user menu is completely gone. I added drupal 8 weights module and tried to adjust weights but it does not work. i am not using any other menu modules except admin menu. any idiea what else i can try? thank you
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9.1
User interface
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It's likely this issue predates Contrib.social: some issue and comment data are missing.
I also have the same issue. Mine disappeared after editing an existing link to use tokens.