Do you find the text ads in GMail to be annoying? If you do, you can use Firefox to hide the ads from displaying.
This trick uses CSS and the Firefox configuration file named userContent.css . Before we start modifying our userContent.css file, I would recommend that you install an extension named ChromeEdit that simplifies the process of modifying your Firefox configuration files. So before you enter the CSS code listed below, go and install this extension (note: you’ll need to restart your browser after installation, so you may want to bookmark this page).
Now that you have CromeEdit installed, click on the Firefox Tools menu and then click on the menu item labeled Edit User Files. A new window will appear that has five tabs across the top. Click on the tab that is labeled userContent.css. Next copy the CSS code below and paste it into the userContent.css file, then click the Save button.
Now, restart your browser and open GMail – the ads are gone!
The above rules make use of the *!important* property value to override any rules that may already exist within the page that is being loaded. In the first rule, GMail has an element with an id of rh and we are setting the tables that have a class equal to metatable within that element, to not display (ie . display:none)
A word of caution, we are only hiding the ads from displaying. They are actually still there, just not visible. This means that Google is still indexing your email messages to provide you with “targetted ads”. It is also worth noting that as this hack is based upon creating CSS rules for existing GMail code, it is very possible that this hack will break as GMail continues to evolve.