3.14.1 I asssume?

Oh I think I found the Launch button but it was hidden down at the bottom.

Created attachment 309202 [details]
Relevant art: a screenshot of Google Play Store

It seems that the problem has been caused by the button being difficult to find for the users. The solution would be simply to move the Launch button next to the Remove button. The change will be simple from the developer's point of view but needs approval from the designers.

See the screenshot of the same solution in Google Play Store (Android).

(In reply to Rafal Luzynski from comment #3)
> ... The solution would be simply to move the Launch button
> next to the Remove button.

Seems like a good idea to me. My only concern is that the destructive and suggested button styles might lose their meanings. It might be best to drop the style from one of the buttons?

I agree, having both destructive and suggested styles would be shouting. Install and launch should keep the suggested style and remove would become a normal button.

Created attachment 311337 [details] [review]
The patch that should fix the problem

Should be committed after freeze (if ever) but you can test already.

What's new:

- Launch button moved,
- its show/hide code moved to another function because it must be strictly synchronized with some other widgets: Remove button state, Remove progress spinner, Install pending label,
- "destructive-action" style removed from the Remove button unless the Launch button is not visible,
- spacing between the Remove and Launch button increased from 6 to 12 to be the same as between the buttons in the bottom of the page,
- sizing group added to ensure the buttons have the same size.

Created attachment 311343 [details]
Here is how it looks like now

(In reply to Rafal Luzynski from comment #7)
> Created attachment 311343 [details]
> Here is how it looks like now

Looks good to me!