Missing PHP extensions on installation break the markup

When installing D8 the user is presented with an error if some required PHP extensions are missing.
This error message is displayed as HTML code and not as rendered HTML.
After some searching I found out that the problem happens because of system.install:118 where a concatenation with a string previously passed from t() happens. The concatenation introduces a <ul><li>.....</ul> list that breaks the output. (see attached screenshots)

I tried to overcome the problem with many ways, but I couldn't do so while maintaining the list. So I attempted to change the output to something simpler, though still easy to read and understand by the end user.

The attached patch solves the problem.
I hope you like the approach