Drupal 8 Equivalent of Drupal 7's disabling a module without Uninstalling it I noticed that I can't just "disable" a module in Drupal 8. As disabling it deletes all the config data of that module and completely uninstalls it. There are times I just want to disable a module to see if that is causing issues, but I have no way to keep its config data intact like how D7 can just disable, but not uninstall. 

How would one do something like this in D8?
https://www.drupal.org/node/2225029

The long and the short of it is that you cant. This option is no longer available in Drupal and it was a conscious decision to remove the ability to disable a module because:


  
  Because upgrades of some contrib module don't actually work (and can't be made to work) if upgrading when they are disabled.
  Because data left behind by a disabled module that is later re-enabled causes integrity issues and cruft.
  Some upgrades left behind data loss due to things like unexpected dependencies, plugins or hooks being unavailable at key times - when
  things were disabled. .. that issue (https://drupal.org/node/1199946) is several hundred arguments long,
  so It's unfair to over-summarize.