Selection clipboard behavior

On Linux, the so-called “PRIMARY selection” exists, which acts as an additional clipboard that stores data when text is selected and pastes it when using a middle-click. This is in contrast to the “CLIPBOARD selection” which stores data using CtrlC and pastes it using CtrlV. The copy and paste actions can also be initiated differently, but these are the most common ways to use these.

The script option autoSelectCopiesToClipboard controls whether or not automatic selections (those not initiated by the user) get stored into the “PRIMARY selection” for some usual cases, and the options tabSwitchCopiesToClipboard and autoCompleteCopiesToClipboard control which other cases of automatic selection affect the “PRIMARY selection”.

Enabling these options is undesirable if you e.g. select some text to paste it into some website, open a new tab, enter a URL, then something gets automatically selected, and you lose whatever you selected before because the “PRIMARY selection” got overwritten. This behavior is being discussed on Bugzilla Bug 1653191.

The README and the web app explain in detail, what these three options do.