When using an Input Method Editor(IME), pressing escape to perform actions in the IME is common. However, if this was done while replying to a comment, the "close on escape" feature was also triggered which cleared the current textarea and closed it.
This change checks if an IME is in use by binding the `compositionstart` event to the reply text box and setting a flag if it's triggered. The "close on escape" feature will now only be triggered if this new flag is not set after typing a reply.
Props BettyJJ, sabernhardt, alexstine, konradyoast, audrasjb, rafiahmedd, afercia.
Fixes#54548.
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