Please describe your issue in as much detail as possible:
For pre-purchased games, where there is no "Install" button on the game page in the Library, the note about the Proton version gets cut off in the UI.
For games with the "Install" or "Play" button the note box is taller and the text fits without being cut off.
This may be related to HiDPI displays, I have "Enlarge text and icons based on monitor size" option enabled in the Settings and the display is UHD (the UI is scaled up 2x).
Hello @Lastique, this section of the Steam's Library view has been overhauled since this issue report was filed and should no longer be relevant to the current Steam client.
Your system information
Steam client version (build number or date):

Distribution (e.g. Ubuntu): Kubuntu 18.10
Opted into Steam client beta?: Yes
Have you checked for system updates?: Yes
Please describe your issue in as much detail as possible:
For pre-purchased games, where there is no "Install" button on the game page in the Library, the note about the Proton version gets cut off in the UI.
For games with the "Install" or "Play" button the note box is taller and the text fits without being cut off.
This may be related to HiDPI displays, I have "Enlarge text and icons based on monitor size" option enabled in the Settings and the display is UHD (the UI is scaled up 2x).
Steps for reproducing this issue: