If you still haven’t switched to Adobe’s subscription plan and still use Lightroom 6, be careful with the updates. The recent reports from users say that Adobe Download Manager has deleted Lightroom 6 from their computer and replaced it with Lightroom CC. You can prevent this by changing some of the settings instead of using the default ones.
If this has already happened to you, don’t panic. You can still get Lightroom 6 back if you don’t want to switch to the subscription software, and Adobe has shared the steps you need to take.