Random seed does not deliver random numbers

Maybe you share similar memory problems as mine. You contributed to some discussions of this topic over the last few years!

Here are some hastily selected examples after googling strings like 'arduino serial monitor cannot copy'.

It appears to vary by IDE version. There are other (presumably unrelated) issues about the first line of print sometimes being missing or corrupted.

Bottom line on this side issue: I'm fairly sure it's because I'm printing at such a fast rate. Even though the monitor is frozen it can then continue to update, blocking selection and copying.