Loramir

Same for me as Krunoslav said. I haven't used the clipper at all lately, but Firefox has been freezing and crashing like crazy lately, and extremely slow. I uninstalled the clipper and it seems to be back to normal. I'm on FF 33.1. I also use 64-bit Firefox Nightly build, which I think is on version 37, and had the same issue - though Nightly has implemented multi-process architecture, so I was getting individual tab crashes right and left instead of the whole browser, which have stopped after uninstalling the clipper.

Krunoslav, I switched to this as a replacement for Download Manager (S3) - seems to work fine with the Web Clipper and does basically the same stuff as Download Manager (S3). Having tried out the Web Clipper a few times, I found an issue with selection clipping (which I think is supposed to work in this release?). If I select text and then use the context menu to clip the selection, it works fine and sends it to my default notebook. If I use the toolbar button and tell it to clip the selection, it creates a note with the correct title but with no text, only a .acgi file attached to it. I tried opening that file in Notepad just for curiosity, and it appears to contain the HTML code of the entire page I was clipping from. I tried this on several different sites with the same result. Clipping as an article or simplified article seems to work fine, so for right now I have to clip the whole article and go in and manually delete the bits I don't want. Another thing - I miss the way the Chrome extension would give you a link to your note after it finished clipping. This one doesn't seem to (yet, anyway), so to check on whether the clip worked correctly or add a tag I forgot, I have to keep Evernote open and keep refreshing it every time I clip something.

After much disabling and re-enabling extensions, I've found the conflict - apparently the Web Clipper and Download Manager (S3) don't like each other. I can live without that, though, and the Web Clipper looks great, though I haven't tried it much yet.

Having the same problem as Krunoslav earlier in the post - the beta version (6.0 alpha 16 from the note updated August 21) is showing up in my addon manager but no sign of it anywhere else in Firefox (version 31.0). No context menu entry, no toolbar icon, no icon in my customize menu. It did give me a notification that the extension was installed successfully but did not require a Firefox restart. I've uninstalled the extension, reinstalled, restarted Firefox in between, made sure both Firefox and everything Evernote related (Windows app, etc) were closed in the task manager.