diffuse from flathub: -t does not work

[Ansa211]

I am running diffuse through flathub, version 0.8.2. The -t switch for starting a new tab seems to have stopped working. I don't know when exactly, but probably with the latest update.

[MightyCreak]

Thanks for opening an issue, I'll take a look at it whenever I can.

[glasswings]

I confirmed that this has the same root cause as #214 by bisecting the behavior of

diffuse CHANGELOG.md -t README.md

In 0.7.7 you'd get two tabs, each one compares a file's working version to its head version. After 8e32f88 diffuse compares the files to each other.