[Browser Isolation] ELI5: Clarify jargon and add inline definitions across RBI root pages

[Oxyjun]

Summary

Adds inline definitions and context for technical terms across all 7 root-level pages in the Remote Browser Isolation section. These pages serve a mixed audience (IT admins, security teams, decision-makers) and used several terms — NVR, WebRTC, rasterization, WebGL, SAML HTTP-POST bindings, DOM access — without explanation.

Changes were generated using the ELI5 skill and verified through an adversarial review that checked every net-new claim against existing documentation.

Key changes by page:

• index.mdx — Inline definitions for "active webpage content," "zero-day attacks," "Secure Web Gateway," and "Zero Trust Network Access." Broke the dense opening paragraph into two for readability.
• canvas-rendering.mdx — Defined "HTML5 Canvas API," "rasterized bitmaps," "NVR," "offscreen texture," and "compositing" inline on first use.
• extensions.mdx — Added context explaining why local extensions cannot interact with isolated pages. Defined "DOM access."
• isolation-policies.mdx — Added parenthetical for Accept: text/html*. Added introductory sentence to Policy Settings explaining the data-loss-prevention purpose.
• known-limitations.mdx — Defined NVR, WebGL, H.265/HEVC, Yubikey/WebAuthN, SAML/HTTP-POST bindings inline. Clarified "Browser Isolation does not support HTTP" → "Browser Isolation requires HTTPS." Added WebRTC context to Brave section.
• network-dependencies.mdx — Defined "remoting client" and "WebRTC" inline. Added explanation that WebRTC uses UDP and does not flow through HTTP proxies.
• accessibility.mdx — Fixed missing space typo.

Documentation checklist

• The change adheres to the documentation style guide.

[github-actions]

This pull request requires reviews from CODEOWNERS as it changes files that match the following patterns:

Pattern	Owners
/src/content/docs/cloudflare-one/remote-browser-isolation/	@codyanthony850, @cloudflare/pcx-technical-writing, @cloudflare/product-owners

[github-actions]

Preview URL: https://b210231a.preview.developers.cloudflare.com
Preview Branch URL: https://jun-eli5-rbi-root.preview.developers.cloudflare.com

Files with changes (up to 15)

Original Link	Updated Link
https://developers.cloudflare.com/cloudflare-one/remote-browser-isolation/known-limitations/	https://jun-eli5-rbi-root.preview.developers.cloudflare.com/cloudflare-one/remote-browser-isolation/known-limitations/
https://developers.cloudflare.com/cloudflare-one/remote-browser-isolation/canvas-rendering/	https://jun-eli5-rbi-root.preview.developers.cloudflare.com/cloudflare-one/remote-browser-isolation/canvas-rendering/
https://developers.cloudflare.com/cloudflare-one/remote-browser-isolation/	https://jun-eli5-rbi-root.preview.developers.cloudflare.com/cloudflare-one/remote-browser-isolation/
https://developers.cloudflare.com/cloudflare-one/remote-browser-isolation/isolation-policies/	https://jun-eli5-rbi-root.preview.developers.cloudflare.com/cloudflare-one/remote-browser-isolation/isolation-policies/
https://developers.cloudflare.com/cloudflare-one/remote-browser-isolation/network-dependencies/	https://jun-eli5-rbi-root.preview.developers.cloudflare.com/cloudflare-one/remote-browser-isolation/network-dependencies/
https://developers.cloudflare.com/cloudflare-one/remote-browser-isolation/accessibility/	https://jun-eli5-rbi-root.preview.developers.cloudflare.com/cloudflare-one/remote-browser-isolation/accessibility/
https://developers.cloudflare.com/cloudflare-one/remote-browser-isolation/extensions/	https://jun-eli5-rbi-root.preview.developers.cloudflare.com/cloudflare-one/remote-browser-isolation/extensions/