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You know what — I just had a thought... What if this is nothing to do with Illustrator, but is instead something to do with my Mac OS's system-level clipboard?
I actually had a 3rd-party multiple-item clipboard item installed some time ago, but then never used it. Maybe there's still remnants of that floating around and that's interfering with it somehow?
I'll see if I can clear out all traces of it and see if it makes a difference... Fingers crossed!
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So it turns out I was right... It *WAS* a 3rd-party multiple-items clipboard app that was interfering with things when copying something into Illustrator's memory.
This app was set to launch at log-in, so it was there running the whole time, even though I wasn't using it!
I feel like an idiot for not thinking about that right off the bat.
So I killed the app and tried it again in Illustrator, and oh joy of joys, I can copy and paste live editable gradients again!!!
So with that issue solved now, I both apologise to you all for wasting your time with my own stupidity and I also thank you for your dedicated and helpful responses regardless!
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