C-M-k, C-M-l can not pass to emacs with Rime about weasel HOT 2 OPEN

What do you use for Meta key? If you use Alt key, it should possibly work. (revised: Control+Alt+x are also system shortcuts in Windows. Shift+Control+x are the only safe three key combinations that can be processed by the IME.)
Weasel does not use Windows keys (as Rime key code Super) mainly because it's used as system shortcuts, which usually take higher priority than the IME.
A guess: C-M-k might have been wrongly recognized by the IME as Control+k, while Super is discarded. Control+k in turn is defined in Rime as a shortcut to delete selected user phrase. That might be why it's not passed down to Emacs. Would you please try removing this line in your %APPDATA%\Rime\default.yaml:
https://github.com/rime/brise/blob/master/default.yaml#L110
?

from weasel.

Thank you for your response.
I am using RIME and Emacs on Windows 10 machine.
That line you pointed out was actually commented out when I was trying to figure out why it did not work; and commenting it out does not make C-M-k be able to pass to Emacs.
I use Alt as Metakey in Emacs.
When RIME is active, my Emacs can detect C-k when I press C-k but can not detect C-M-k, when I press C-M-k. I tested with C-h k in Emacs trying to catch the following key-pressing.
C-M-k works fine when I switch to other input method, so that I am assuming it was RIME blocked that key someway I do not know.

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