red diagonal ghosts while using pen tool

[guy.cruls]

All too often, ugly fat red diagonals appear when I click/creating a point with the pen tool.

The diagonals originate in the points created - see image below.

Remedy, anyone?

Many thanks!

[Doug A Roberts · Accepted solution]

View > Preview on CPU, or click the rocket icon and disable GPU performance entirely.

[guy.cruls]

many thanks.

when I went back to Ai, the diagonals did not reappear, but they would've done sooner or later.

good to know of the GPU disabling to get rid of these ghosts.