A resolution was made for csswg-drafts/#7542.

[css-ui] ? Allow <textarea> to be sized by contents.

• RESOLVED: Add a new property (provisionally "form-sizing: normal &124; auto") that turns off the "half-replaced" sizing of form controls and makes them content-based like normal elements

Discussion.

(In reply to Mozilla Apprentice from comment #0)

(provisionally "form-sizing: normal &124; auto"

(this was broken via some bot-copypasting-around encoding conversion; it should read:
form-sizing: normal | auto

(We should wait on spec text / finalized naming before diving too far into this. I think IanK is working on a prototype of this in Blink and he said it wasn't too much work, for what it's worth.)

This has changed to be field-sizing with values of fixed and content. See https://drafts.csswg.org/css-ui/#field-sizing

Chrome intent to ship: https://groups.google.com/a/chromium.org/g/blink-dev/c/MjCCRQo9Qk0/m/XTjOSVDcAAAJ

Is there any ETA on this feature? It saves a lot of time in my use case and would like to avoid having to do a workaround for firefox.