How to fully expand Firefox headers in f12 developer tools

Question

I was doing a little debugging for my web application, and wanted to test out an API endpoint in Postman, so I opened up F12 devtools, and looked at my API request.

In order for Postman to work, it'll need an auth header, so I just grabbed the one from my browser, and pasted it into Postman.

I've done this for years, because it's quick and easy, and I've never had any trouble before - on Ubuntu or Windows, and not in Chrome on MacOS either.

But when I pasted it in to Postman, the API call failed:

Error: Invalid character in header content ["Authorization"]

I initially thought maybe I had a trailing space, or newline, but I couldn't see anything wrong with it. So I looked closer:

Weirdly, this bug only happens when I select the value (or any part of the value). It does NOT happen if I triple-click and select the entire value.

I would love if this was not the case.

I don't have my Windows/Linux machine to test on right now, but I'm pretty darn sure this only happens on Mac, because I've never had this happen to me in the past.

Does anyone know why this happens, and is it possible to disable it? I always want to see the full-sized headers in dev-tools.

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I'm using Firefox 132.0.2 (aarch64) on MacOS, with no significant addons or extensions (just adblock).