During the installation of any extension, the installer script can display its own message, including HTML content (which most extensions do). Since 3.4.0 the contents of this message is forcefully bold. I believe that #5729 introduced this.
Steps to replicate it
Install any extension that provides a HTML message upon installation. You'll notice that the whole message is wrapped in <strong> tags.
Proposed fix
It's simple: remove the <strong> tags that are wrapping the message supplied by the installation script. I have left the <strong> tags that show up when displaying the XML <description> tag since most people don't use HTML in there so it shouldn't be a problem. The non-bootstrapped version (before the PR) did display the description in <th> tags and the message in <td> tags, so I'm following what was already in place.
As I said in my original post, <th> was in place before the change was introduced, so the <description> tag was indeed bold. I think we should keep it this way for now.
joomla-cms-bot
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@OctavianC do you think we need also remove the
<strong>on line 19 in the same file?