Hey there,

do any of you know a simple way of finding out if a user has Greasemonkey installed or not?
Obviously I mean when writing a website.

Thanks!!

yeah, Tools->Addons ;-D

by what means are you trying to determine? from a web page? from an applet? unless you get them to install something I see no way that it would be possible. firefox doesn't send extension information every time you load a page. and you should know greasemonkey is in its own sandbox. however, if a particular script was written poorly I believe you could tell from the website its running on, but that's about it

FF won't tell you which extension has been installed, but if a GM script is running on your page you can detect some secondary effects like document change. Here an interesting article:

http://www.oreillynet.com/pub/a/network/2005/11...

you still running version 0.3? please correct me if im wrong, but the sandbox is much more secure now than in 2005. can't detect anything unless youre using unsafeWindow to my knowledge. and even then i am pretty sure your call will just get hijacked, not so much a detection

I have a webpage, and for all users who have not yet installed Greasemonkey I like to display some box.

I know that Firefox sends some sort of information, as you can see on the Firebug-warning that GMail uses.

This is how one person does it, I can't get it to work myself with greasemonkey.

http://ha.ckers.org/weird/firefox-extentions.html

Oh, that's good.
Web Developer Recognition seems to be out of date, though.

But you're right, I can't really get it to work either:
<img src="chrome://greasemonkey/content/status_off.gif" alt="" onload="alert('you have it!');" />
does not do anything...

The bug that enables that kind of detection (using chrome urls) has been recently fixed. It wouldn't be possible to do that with Firefox 3. See http://adblockplus.org/blog/web-pages-accessing...

I have heard of the bugfix. They are able to access that I am using IETab in my ff3b5. Is this feature scheduled only for the final version of FF3?

The question is why does it still work with some of the addons, as seen in the link above?

I believe the bug was fixed after beta 5 was released, so the code won't work with Firefox 3 RC1 or recent nightly builds (not sure, though)