User-Agent: Mozilla/5.0 (Windows NT 6.0; rv:2.0b8pre) Gecko/20101007 Firefox/4.0b8pre Build Identifier: Mozilla/5.0 (Windows NT 6.0; rv:2.0b8pre) Gecko/20101007 Firefox/4.0b8pre "Clear Recent History" does not remove data that has been stored for offline use. Reproducible: Always

STR: 1. Go to a site that populates persistent storage (e.g. click "play" & load on http://www.unrealengine.com/html5/). 2. Check fxprofile/storage/persistent/ for "http+++www.unrealengine.com" (size > 100MB). 3. Clear recent history -> offline website data. 4. Repeat step 2. Actual: Folder still there with same size. Expected: Folder deleted. That's a major boo-boo (and should be really easy to fix), stumbled upon this when inspecting wasted space on my machine and saw that Monster Madness / playverse.com used >760MB without a quick and obvious way to delete that data (except for visiting the site again -> site info -> permissions -> clear offline data).

Sorry, wrong component. STRs were with clear recent history from "last hour".

(like bug 436248 — maybe a duplicate?)

See also Bug 527667. Will check later.

Not only the Web Storage API (localstorage), but also the IndexedDB API seems to use the persistent storage folder. I don't know if this changes anything, but I figured I would add the comment.

Why nothing can clean and delete these folders inside profile (unless manually)? storage |-persistent |-http+++example.com |-idb |-.metadata |-[...] |-temporary |-http+++example2.com |-[...] E.g. You may be downloading big files from Mega and something make the download fail and the big incomplete files will stay inside those folders forever. Eventually using much more space than the defined cache limit. Other sites create those folders for almost no reason, and more folders start accumulating there. Imo, this problem is severe and too old already.