Summary

Draggable legend gets stuck to cursor after scrolling while hovering the artist. To 'unstick' it, it is necessary to left click. I believe the expected behavior is to only drag the legend while holding the left mouse button. If that is not the case, please close this issue.

Proposed fix

Sample code:

import matplotlib.pyplot as plt

plt.plot([],[], label='scroll over me, then move the cursor')
plt.legend(draggable=True)
plt.show()

I believe the issue is that the class DraggableBase (at line 1425 of matplotlib/offsetbox.py) uses a 'pick' event to grab the artist, which I believe includes scrolling events. It might be possible to return from a false positive pick by checking that the pick event is a mouse click instead of scrolling at DraggableBase.on_pick. Another alternative is to change the pick event to a button_press event.