Running Firefox 3.6 on two machines.
OS X 10.6.2
Running the Web Developer 1.1.8 toolbar:
The Web Dev toolbar and 1Password work fine together, however, every time I upgrade 1Password, the Web Developer toolbar is disabled with a note saying it's not compatible with FF 3.6. It is, and I can simply uninstall it and reinstall and everything is fine, until the next 1Password update.