mcedit .local/share/mime/text/x-geany-project.xml

"~/.local/share/mime/text/x-geany-project.xml"

<?xml version="1.0" encoding="utf-8"?>
<mime-type xmlns="http://www.freedesktop.org/standards/shared-mime-info" type="text/x-geany-project">
  <!--Created automatically by update-mime-database. DO NOT EDIT!-->
  <comment>Geany project</comment>
  <icon name="geany"/>
  <glob-deleteall/>
  <glob pattern="*.geany"/>
</mime-type>

mcedit .local/share/mime/packages/application-x-geany.xml

"~/.local/share/mime/packages/application-x-geany.xml"

<?xml version="1.0" encoding="UTF-8"?>
<mime-info xmlns="http://www.freedesktop.org/standards/shared-mime-info">
    <mime-type type="application/x-geany">
        <comment>Geany project</comment>
        <icon name="application-x-geany"/>
        <glob-deleteall/>
        <glob pattern="*.geany"/>
    </mime-type>
</mime-info>

mcedit .local/share/mime/packages/x-geany-project.xml

"~/.local/share/mime/packages/x-geany-project.xml"

<?xml version="1.0" encoding="UTF-8"?>
<mime-info xmlns="http://www.freedesktop.org/standards/shared-mime-info">
    <mime-type type="text/x-geany-project">
        <comment>Geany project</comment>
        <icon name="geany"/>
        <glob-deleteall/>
        <glob pattern="*.geany"/>
    </mime-type>
</mime-info>

update-mime-database    ~/.local/share/mime/