Best way to give clients browser-based terminal access? Is xterm.js still the go-to?

I’d like to give some of our clients terminal access straight from the browser, so they don’t have to install SSH clients or set up keys.

So far, the plan is xterm.js on the frontend, plus a Node.js backend using node-pty over WebSockets. Before I commit, I’d like to hear from people who’ve built something similar.

**What I need:**

* Clients connect to their own server / an isolated container / a shared dev environment
* Log in through our existing web app / SSO, with per-client access control
* Roughly 50 concurrent users

**My questions:**

1. Is xterm.js still the best frontend choice, or is there something better now?
2. Would a ready-made tool make more sense than building my own (ttyd, Wetty, Apache Guacamole, Teleport, etc.)?
3. What security problems should I watch out for when exposing a shell through the browser (isolation, session hijacking, resource limits)?
4. Are there problems you only ran into in production, like reconnects, latency, copy/paste or resizing?

Any experience or tips are welcome. Thanks!

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