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I copy & paste to and from Notion very frequently.
Currently it's maddening because there's a delay between the time I can see visually that text is selected (Notion shows it with blue background) and the time copy command (Cmd-C on Mac) will copy the text to clipboard.
It should happen immediately.
The issue seems to be that Cmd-C is only active when this pop-up is shown:
The problem is that showing this pop-up is delayed. Cmd-C should work immediately after I can see that the text is selected (has blue background).
Here's an example screen recording where I select text (shown in blue) and quickly press Cmd-C and Cmd-V:
Instead of copying just the selected text (in blue), the whole block was copied.
But this is also an issue when copying between Notion and other apps, like text editors.
Here's a simple test for this issue:
1. Open a text editor next to notion window.
2. Select text with mouse (blue highlight). Wait. Cmd-C to copy. Switch to text editor and Cmd-V to paste. You should paste the selected text.
3. Now select text and Cmd-C immediately. Switch to text editor and Cmd-V. For me, when I press Cmd-C at my normal speed, I get the old selection pasted, not the new one.
(It's Ctrl-C and Ctrl-V on Windows).