Why is copying and pasting a block now broken?

[WagmoreBarkless]

This is trivial, but...

Henceforth, if I had a block of code:

code line 1
code line 2
code line 3
code line 4

And I wanted to copy the 2nd and 3rd line to another block, I would just select them both, Ctrl+C, move caret, Ctrl+V, bang, life is good. Now, however, when I select the two lines together, I see blinking black vertical bars at the end of the lines when I select. I copy, move caret, and paste, and I get bizarre and unexpected behavior WRT inserting blank lines, copying only one line, etc.

Either I have somehow offended the gods (I'm sorry - honest!) or I have bumped a switch that I can't find.

How can I turn this alleged 'feature' off?

Thanks.

PyCharm 2021.2 (Community Edition)
Build #PC-212.4746.96, built on July 27, 2021
Runtime version: 11.0.11+9-b1504.13 amd64
VM: OpenJDK 64-Bit Server VM by JetBrains s.r.o.
Windows 10 10.0
GC: ParNew, ConcurrentMarkSweep
Memory: 1920M
Cores: 6

[Larz60+]

Either I have somehow offended the gods (I'm sorry - honest!) or I have bumped a switch that I can't find.

I think you have, I can copy with no ill effects.