@MojangSupport the launcher for Linux says there's a new version of the Launcher, the link is slightly wrong; it has a space (/alternative%20) and the Minecraft.deb file isn't updating the launcher.
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Replying to @Gone25122020 @AvisPhlox
Hi. I can't see it on minecraft.net/download/alter…. Can you please provide some more details? ^DS

Apr 24, 2019 · 7:58 AM UTC

1
Replying to @MojangSupport
Launcher > See Options link > Error Page. But the major issue was installing the Minecraft.deb file wasn't updating the launcher. I downloaded the raw tar.gz files and copied them to /opt/minecraft-launcher/ replacing the old ones. It took time but I had to do it manually.