Detail this asset from Unity Store: Original Link
This is a paid asset, but now you can download Animation/FX Previewer Free.
AnimationFX Previewer v1.0
A must have animation preview extension for all.
This extension let you preview any animated character or object in editor mode directly,
Yes you don’t need to run the game!
This is so handy when you edit some big scene, you want to view the animation in edit mode, any time any where.
Another great feature is the plugin also supports sync particle FX time to animation, imagine that when you want to make a character skill FX, it’s hard to match the particle FX time to the skill animation frame, this plugin comes to the rescue.
Play animations directly in editor mode
One window to handle all logic.
Drag-drop, Preview, Set, Done.
All animations are listed for preview.
Drag slider to preview animation by frame.
Play animation/FX forward/backward easily.
*The sample assets in the screenshot are not included!