I have poked around a bit in about:config in the past to do this and it worked but about a month later it stopped doing this and now it will only cache 25% of video and stop. I don't have very good connection and some severs I connect to might be slow but this is no reason why video cache stops or auto deletes when I click a head to try to cache more. I don't want an add on I just want a fix via about:config. I told readahead limit to 90000 but won't read ahead.... I'm not very happy with Firefox cause I spent a lot of time typing out a long email to Firefox from app store email address but I guess its far too hard to email people but I guess if someone joins your site it kinda makes you money so I see where FF community stands on actually being real with people. I hate forums so I'd like to solve this issue asap.