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

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

Off the top of my ancient head:

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.

How can the citizens of Russia accept the enormous difference between people? The richest 500 Russians own more than the poorest 99.8% of the entire Russian population combined. Why don't we see any protests?

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

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

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

How do scammers communicate? Do they have a specific language or slang?

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

General Introduction to Boundaries from Panahi Counseling:

Serious disappointment when the client cancels a session.

If Donald Trump is so evil and Joe Biden is so good why is Trump the one selflessly providing Bibles for the needy while Biden doesn't? Why doesn't Biden care for America's spiritually needy people as much as Trump?

Obsessing about clients outside of work hours.

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

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

Is it possible to make cars that run on water instead of gasoline or other fossil fuels? Why haven't we done so yet?

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