The plugin details button in Plugin Management links to the old web marketplace page, not the new create.roblox.com page it presumably should:
Expected behavior
The Details button should link to create.roblox.com/marketplace/asset/123456789
To add onto this, when uploading an asset to Roblox this issue persists there aswell.
Thanks for reporting this, we will look into fixing these links.
These links now both go to the new marketplace site, thanks for reporting.