Description
The issue arises due to how Coliru works - As long as Coliru works like this, I can't do much more.
Basically, the addon checks for the src key/value pair in the request URL.
If found, sets the value as the session code for Coliru.
If the last Coliru page contains a src key/value pair and the addon is disabled afterwards, all Coliru pages will store the last key/value pair.
To erase this pair, you can reenable the addon and load a clean Coliru page (with no key/value pair).
Note: The previous session code is lost every time you load a Coliru page while the addon is enabled.
Code injection doesn't seem to have any effect for Coliru, since its code uses local variables, and this is the only way to "push" custom code into Coliru from external sources.