Hello,

A user who uses the inverted high contrast theme reported that in
the application menu, the firefox icon is not getting its inverted
high contrast variant. Apparently, this is because we are using
firefox-esr.desktop, which references the firefox-esr icon, and
mate-themes only provides a firefox icon. I guess the firefox.png icons
could be duplicated into firefox-esr.png icons? Possibly even in
upstream?

Samuel