Comment 7 for bug 1876467

I think the problem is with the nm-signal-*-secure.svg images found in at least Ambiant-MATE and Radiant-MATE themes.

With strace I can see that 'mate-indicator-applet-complete' tries to open '/usr/share/icons/Ambiant-MATE/status/22/nm-signal-75-secure.svg' but after that it displays '/usr/share/icons/Humanity/status/22/image-missing.svg' instead.

Opening '/usr/share/icons/Ambiant-MATE/status/22/nm-signal-75-secure.svg' with Inkscape dispalys multiple errors like this:

nm-signal-75-secure.svg:34: namespace error : Namespace prefix inkscape for current-layer on namedview is not defined
kscape:zoom="10.375" objecttolerance="10.0" pagecolor="#ffffff" showgrid="false"

Opening with cairosvg prints:

xml.etree.ElementTree.ParseError: unbound prefix: line 34, column 2

A Workaround that works for me: Inkscape, beside the errors, can open the images and by saving them, overwriting the originals, fixes the missing image problem.