I created a web session and browsed to a website. If I wanted to grab a text, I would right-click on the text but "Describe", "Get Text" and "Show Table" options were disabled in the menu. Regardless of where I right-clicked these three options never became enabled. I also tried right-clicking on a table and couldn't get "Show Table" to work.
Next, I created a web test case on a Windows machine, moved the test case to the same linux box and could not get the test case to work. It seems like a compatibility issue with this particular version of linux.