Mytabs not showing in ACP

So, I installed mytabs on mybb 1.8 but the problem is the author asked to not activate the plugin from plugins tab in admin cp,

Just go to forums and posts and there I should be able to find mytabs on the sidebar. But for some odd reason I am unable to find mytabs on my acp. Please help me how to install mytabs> on mybb. I tried using both of the mytabs,

https://community.mybb.com/mods.php?action=view&pid=456

and

https://community.mybb.com/mods.php?acti...w&pid=1337

Any help someone? Or is the forum dead already>

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Fixes I tried but didn't worked,

I tried changing php version from 8 to 7.4 and still it is not showing in forum and post tab in ACP. How to get it working?