Recent Minecraft Launcher update will not launch older versions of Minecraft.

After a forced upgrade to new launcher; Versions other than 1.13 do not launch.

Minecraft.Jar also does not work.

EDIT:  Able to get it running using the Java version and installing libgconf2-4 (SNAP version still does not work)

EDIT2:  While the Java version is now working, it states that "The authentication servers are currently down for maintenance"... Which is not the case as my Windows machine is able to launch and connect.

EDIT3:  If Optifine is installed; it will not launch. (1.12.2 - OptiFine_1.12.2_HD_U_D2)