Does a filename in Ubuntu starting with "readme" automatically become a readme document type?
html and scripts are also plain text so the file type hasn't changed, just weird mojo about subclass icon decisions,
I found something that may help you:
Save the following as jsp.xml
:
<?xml version="1.0" encoding="UTF-8"?>
<mime-info xmlns='http://www.freedesktop.org/standards/shared-mime-info'>
<mime-type type="text/x-jsp">
<comment>JSP file</comment>
<glob pattern="*.jsp"/>
</mime-type>
</mime-info>
Then open a terminal and run
xdg-mime install --novendor jsp.xml
Now all files with the extension .jsp
should have the MIME type text/x-jsp
.
See Shared MIME-info Database if you want to learn more about how MIME types are defined.