Nano issue after Ubuntu 18.04 issue?



After Ubuntu 18.04 upgrade, I noticed that the nano editor behaves strange when showing repeated characters in a word.

E.g. …


… shows as …


The magic starts only after 7 chars are identical.
When moving w/ cursor above, the hidden chars reveal gradually.

Other Ubuntu 18.04 installations don’t do that.

Google didn’t help.

Any ideas?