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

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.

General Introduction to Boundaries from Panahi Counseling:

What should I do if a girl whom I love asks me to be her friend?

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

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

Serious disappointment when the client cancels a session.

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

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.

Can you fly an American flag in the UK in your own private property there? What is the UK’s government stance on that? And if yes, do you also have to fly the UK flag or the American flag can fly solo?

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.

Obsessing about clients outside of work hours.

Why did my ex-narcissist move so fast with his new supply marriage engagement moving in, etc.?

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