What are some signs that a therapist may have poor boundaries with their clients?

Struggling with fantasies of deeper connections with clients, whether sexual or parental or other intense or intimate relationships beyond psychotherapy.

Disclosing feelings, fantasies, and experiences to the client in ways not related to the work the client is engaged in.

These items can happen fleetingly, briefly, in any therapy, but if they’re frequent, it’s definitely time for the therapist to get some good, solid supervision/consultation.

A kid threw a stone at my car. I confronted his mom (who was nearby). She said, "You can't prove it was my son." How should I have reacted?

Routinely going over the time limit with certain patients, compromising the time for the next client.

Eager anticipation (or anxious anticipation) of the next session in ways that distract.

Failing to mention the client in supervision/consultation, out of fear the supervisor/consultant will advise return to ordinary healthy boundaries.

Stolen iPhones disabled by Apple's anti-theft tech after Los Angeles looting - TechSpot

Serious disappointment when the client cancels a session.

Sense of competition with persons who are important in the client’s life.

Obsessing about clients outside of work hours.

Why should we share our wife with others?

Off the top of my ancient head:

General Introduction to Boundaries from Panahi Counseling:

Frequent phoning or texting of clients to “check up on them and make sure they’re OK.”

What were Sauron's powers in The Lord of the Rings (LOTR)? Did he have any magic or anything like that?

Session-expressed curiosities about client details not relevant to the therapy.