fix(fuselage): InputBox not stretching to the maximum available width

[nazabucciarelli]

Proposed changes (including videos or screenshots)

InputBox, and everything built on it (TextInput, UrlInput, EmailInput, NumberInput, TelephoneInput, TextAreaInput, etc.) collapses to its min-width instead of filling the available space when it is rendered as a direct child of a flex‑column container (e.g. a fuselage Field, which is display: flex; flex-direction: column; align-items: stretch) rather than inside a FieldRow.

Root cause: v0.79.1 (#2024) added width: 0 to the shared .rcx-input-box rule. A definite width disables the cross‑axis stretch of a flex column item, so the input stops growing to the container width and falls back to min-width: 8rem. In v0.79.0 and earlier the rule had no width, so it stretched correctly.

Fix: Use a main‑axis‑only basis instead of a definite width:

Where it shows: in Rocket.Chat admin settings, every relativeUrl setting (e.g. the OAuth "Callback URL" fields) renders a readonly UrlInput directly inside a Field, and appears collapsed to ~128px with the URL truncated, while sibling text/secret fields (which sit inside a FieldRow) look fine.

• The defect is in the component's sizing contract, not in one call site. width: 0 breaks InputBox for any addon‑less input rendered in a stretch (column/block) container, which is a valid usage. The relativeUrl setting (the one used in apps/meteor/server/settings/oauth.ts) is just the first place it became visible: TextInput, EmailInput, etc. collapse identically there, they are the same component with a different type. Fixing it in Rocket.Chat main repo would patch one symptom and leave the latent bug for every other current and future consumer.

Issue(s)

CORE-2348 [Regression] OAuth callback URL fields render too narrow in admin settings

Further comments

[changeset-bot]

🦋 Changeset detected

Latest commit: 731d8e2

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@rocket.chat/fuselage	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[nazabucciarelli]

We decided to fix it on the main repo, as the defined css width property is needed and shouldn't be changed because it was added to fix a Firefox visual issue. Closing this PR in favor of RocketChat/Rocket.Chat#41105