Have been using X13 on my 8GB mini for 6 months with only one issue: switching between programs might make the cursor disappear when returning to CA. Though i can't remember it happened since moving from Big Sur to Monterey.
Was using X12 on an old Mac Pro 5.1 with Radeon RX580 just fine but Mojave wouldn't run X13
The pasting issue may have to do with the system's private font being unavailable for general use. I too have to paste it into a text editor and copy it again, as I can find no keyboard command for Paste Without Formatting or similar in Chief.
