Thanks David, although bug 86184 is the reverse issue (firefox is supported and other windows not) it gave me the decisive idea. Open ccsm workarounds-plugin, activate 'legacy_fullscreen_support', logout-in - issue solved.
Thanks David, although bug 86184 is the reverse issue (firefox is supported and other windows not) it gave me the decisive idea. Open ccsm workarounds-plugin, activate 'legacy_ fullscreen_ support' , logout-in - issue solved.