▁ ▁The ▁open - source ▁nature ▁of ▁Firefox ▁has ▁made ▁it ▁possible ▁to ▁maintain ▁its ▁development ▁for ▁operating ▁system ▁versions ▁that ▁are ▁past ▁their ▁product ▁support ▁life ▁cycle , ▁and ▁has ▁resulted ▁in ▁Firefox ▁having ▁stronger ▁security ▁and ▁better ▁support ▁for ▁modern ▁web ▁standards . ▁This ▁in ▁effect ▁extends ▁the ▁useful ▁lifetime ▁of ▁devices ▁stuck ▁on ▁older ▁major ▁versions ▁of ▁Android . ▁ ▁Similar ▁to ▁the ▁desktop - ▁Firefox : ▁Version ▁ 6 0 ▁introdu ces ▁the ▁setting ▁DNS ▁over ▁HTTP S ▁and ▁has ▁to ▁be ▁activ ated ▁manually ▁in ▁about : config . ▁ ▁F ork s ▁and ▁code ▁reuse ▁ ▁Ice Cat Mobile ▁ ▁GNU ▁maintain s ▁fork ▁of ▁Firefox ▁for ▁Android ▁with ▁all ▁propriet ary ▁bin aries ▁removed . ▁ ▁F enne c ▁F - D roid ▁ ▁On ▁ 1 ▁February ▁ 2 0 1 5 ▁and ▁beginning ▁with ▁version ▁ 3 5 . 0 , ▁the ▁open - source ▁F - D roid ▁app ▁repository ▁hosts ▁the ▁F enne c ▁F - D roid ▁package . ▁This ▁is ▁a ▁FO SS - only ▁version ▁of ▁the ▁browser , ▁pulled ▁from ▁the ▁un brand ed ▁Firefox ▁source ▁code , ▁lic ensed ▁under ▁M PL 2 , ▁and ▁based ▁on ▁the ▁latest ▁Firefox ▁releases . ▁Part ▁of ▁the ▁package ' s ▁name ▁comes ▁from ▁the ▁mobile ▁Firefox ' s ▁F enne c ▁code ▁name . ▁ ▁M aint ain ers ▁of ▁this ▁version ▁st rive ▁to ▁keep ▁out ▁all ▁propriet ary ▁bin aries ▁used ▁in ▁Firefox . ▁As ▁of ▁version