"Cold launching" Roblox using launch URIs with launch data decodes URL Encoded JSON incorrectly

Attempting to launch Roblox using either of the Roblox launch URIs [roblox://<args> or https://www.roblox.com/games/start?<args>] with URL Encoded JSON as launchData causes it to be parsed/decoded incorrectly.

“Cold” Launch [this is wrong!]

Joining the game with launch data with Roblox closed
image
Where did the quotations go? This isn’t valid JSON!

“Hot” Launch [this is correct!]

Joining the game with launch data while Roblox is already open
image

All subsequent launches with Roblox already open will allow the URL Encoded JSON to be parsed just fine.

I have verified that this also occurs with the vanilla Roblox bootstrapper, so mine is not manipulating the launchData in any way.

Expected behavior

When launching Roblox with any of the aforementioned launch URIs, it should be expected that the URL Encoded JSON is parsed correctly.

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