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

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.

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

General Introduction to Boundaries from Panahi Counseling:

Canelo Alvarez vs. Terence Crawford Lands On Netflix, Las Vegas To Host Superfight - RingMagazine.com

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

Serious disappointment when the client cancels a session.

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

NASA warns: massive anomaly spreads across Earth, linked to mysterious forces beneath the surface - Glass Almanac

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

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.

Judge orders Trump administration to provide due process to some migrants deported to El Salvador - NBC News

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

Off the top of my ancient head:

Obsessing about clients outside of work hours.

How one of San Francisco's most successful new chains 'just kind of happened' - SFGATE

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