Oops... Yes, while replacing a LLFrameTimer with a simpler (and faster) gFrameTimerSeconds comparison, I made a mistake and inverted the subtraction...
Fixed for next release, but since you are using Linux, you may recompile the viewer yourself (just a matter of typing "./buildlinux.sh" in a terminal pointing from inside the linden/indra/ sub-directory of the sources) with line 350 of linden/indra/newview/llpanelminimap.cpp changed to read: