I installed the module on a fresh drupal 9.1.4 and could not see the button as an anonymous:
https://www.loom.com/share/634791ed17bb4d7896c88d1cadeaa2a4
I noticed there was an error in the devtools console.
Add the core/drupalSettings and core/drupal as library dependencies.
review fix.
Fixed
3.0
Code
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It's likely this issue predates Contrib.social: some issue and comment data are missing.
Issue #3196843 by anacolautti, DeepaliJ, VladimirAus: button not showing...
Automatically closed - issue fixed for 2 weeks with no activity.