Hmm, I'm not seeing that behavior. For example, here is the stretchyman example project, the current frame is set to 29, and nothing is selected:
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After pressing ctrl+shift+L
I see new keys added on frame 29 for all the rows, including the paths, that already have keys:
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If you can describe or show where it doesn't work right, we are happy to fix it!
Note that ctrl+shift+L
sets a key for all the visible rows in the dopesheet. You may want to first select nothing (escape
or spacebar
) to show all rows in the dopesheet before using ctrl+shift+L
. If your paths don't have any keys yet then they won't have rows in the dopesheet and ctrl+shift+L
won't set keys for them.