Somewhat confusingly, there was an old launcher called 'Minecraft Unified Launcher', which was specifically for Windows 7 and 8 and only launched Java Edition and Minecraft Dungeons.

Minecraft players struggle to play Java Edition with the new Launcher causing log-in difficulties and long download times.

Minecraft and Minecraft Dungeons can now be offered and accessed through the same launcher, which is now rolling out to everyone via a free update.