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PC - Clown Haste effect permanent if Haste is gained during stun.

Step 1: Enter public match as clown.
Step 2: Toss an Afterpiece Antidote (Yellow Gas) at a survivor at a pallet.
Step 3: Get stunned by said survivor as the Haste effect is granted.
Step 4: If successful, you now have a permanent speed bonus.
When this occurred I was playing as "The Clown" on the newest map "Garden of Joy". I was using Clown's own perks for an Archive Challenge, as well as Shadborn. All perks were Tier III. As of now, I have only had the bug occur once, I shall attempt to reproduce the bug after completing this bug report. EDIT: After replicating the above steps I have successfully replicated the bug.
Since I have started to record all of my games with Shadowplay for content creation, I have a recording of the match which can be found at the YouTube link below:
I will also include my log as I am a PC player.
This link is to my first interaction with the bug:
This link is to my second interaction where I attempted to replicate the bug in a public match. I succeeded.
https://www.youtube.com/watch?v=aypYnBxp95c