I recently tried to install Google ToolBar for Firefox into Flock, but received an error message, “Incompatible Extension Detected” and goes on to state that it is not designed for Flock and if installed could damage the application. Neither of which is true. If you decide to install it anyway, you will get the next error message: “Incompatible Extension – Google Toolbar for Firefox 2.120060807M could not be installed because it is not compatible with Flock.” Which – again – is not true. I am not sure why Google is doing this other than to keep users from switching to Flock, or perhaps go BACK to Firefox if they switched to Flock previously. But why should they care?
Seeing as how I want to stick with Flock, I decided to find a way to make it work, damage or no damage to the Flock browser. Plus I figured I could reinstall Flock if I had problems and delete the Google Toolbar for Firefox extension. So if you like Flock and want to use Google Toolbar, here is what to do:
Google ToolbarBar for Firefox
(available on the web from Google, but only as a web install, NOT a stand-alone installer):

1. Install the GoogleBar into Firefox.
2. Quit Firefox.
3. Locate your Firefox extensions directory (inside ~/Library/Application Support/Firefox/profiles default directory).
4. Locate the Google ToolBar directory (Trial and error: keep opening directories and using TextEdit to read install.rdf files until you find the one with Google in the text.)
5. Copy the Google ToolBar directory to Desktop.
Open install.rdf file inside that directory.
7. Add the following code in the target applications section (also available from Flock developer wiki):
<!– Target Application – Flock –>
<em:targetApplication>
<Description>
<em:id>{a463f10c-3994-11da-9945-000d60ca027b}</em:id>
<em:minVersion>0.7</em:minVersion>
<em:maxVersion>1.0</em:maxVersion>
</Description>
</em:targetApplication>
8. Move this directory into the Flock extensions directory (inside ~/Library/Application Support/Flock/profiles default directory).
9 Launch Flock.

Click to zoom into Google Toolbar for Flock.
Voila! Now just set up the preferences you would like for Google Toolbar and you are ready to use Google Toolbar for Flock.







