Version: 2.80 May 19th release, Linux 64 bit (hash 1fce0460d522)
How to reproduce:
- Create or open a file with some keyframes
- In User Preferences > Input, disable "Release Confirms"
- Select a keyframe in the timeline, dopesheet, or f-curve editor
- Note how the selected keyframe "sticks" unexpectedly to the cursor!
- This bug is consistent whether LMB or RMB is the selector.
This is not the expected behavior! Keyframes, like any other item, should require a click AND drag in order to be moved by the selecting mouse button.