Embiggen .desktop loaded applications on Ubuntu

I keep forgetting the steps required for this, so thought I should write them up in one easy to remember blog post for myself.

My desktop set-up consists of 2 x 1080 and 1 x 4k display. Making sure that applications are readable is a bit of a farce.

But as long as I ensure that certain applications only ever appear on the correct monitor, means that I can alter the launcher to set the correct DPI scaling.

Case in point is the thunderbird.desktop launcher. I only ever use it on the 4k display (central monitor), so I can alter the launcher to pre-set the scaling to two times normal. Making it readable without squinting (I’m nearly 40 you know).

Using locate thunderbird.desktop we find that it’s stored at /usr/share/applications/thunderbird.desktop. So raised privileges will be needed to edit it.

sudo nano -w /usr/share/applications/thunderbird.desktop

Using ctrl+\ to replace text, search for Exec=thunderbird and replace it with Exec=env GDK_SCALE=2 thunderbird. Use ctrl+x to save and exit the editor.

Now when the Thunderbird launcher icon is clicked, the application will be rendered at twice the normal size. Making the working day a lot less squinty.