Primary-source library

Read past the summaries.

These are the standards, implementation notes, and browser-maker instructions used to verify the site's core claims as of August 1, 2026.

Standards and web-platform behavior

• RFC 6694 — The “about” URI SchemeDefines the scheme and the well-known about:blank identifier.
• WHATWG HTML Standard — Matching about:blankThe living-standard definition, including query and fragment handling.
• WHATWG HTML Standard — Window.open()Navigation and new browsing-context behavior.
• MDN — Same-origin policy: inherited originsWhy an about:blank popup or frame can inherit origin from its creator.
• MDN — Window.open()Practical documentation for popup creation and blocking.

Chromium behavior

• Chromium — Special Case URLs: about:blankImplementation nuances: content injection, origin, fragments, history, and initial documents.
• Chromium source — blocked navigation URLDefines the special about:blank#blocked constant.
• Chromium — RenderProcessHost URL filtering interfaceTechnical context for renderer access checks and URL rewriting.

Google Chrome

• Set your homepage and startup pageOfficial desktop homepage, Home button, and startup paths.
• Block or allow popups in ChromeOfficial site-specific popup controls.
• Remove unwanted ads, popups, and malwareMeaningful signs of unwanted software and approved response steps.

Microsoft Edge

• Change your browser home pageOfficial Edge Home button path.
• Block popups in Microsoft EdgeOfficial popup controls and exceptions.
• Microsoft Edge extensions FAQExtension management and organization-policy indicators.

Mozilla Firefox

• How to set the home pageFirefox Home, Custom URLs, and the built-in Blank page choice.
• Restore previous sessionWhy old tabs can return at launch.
• Popup blocker settings and troubleshootingOfficial Firefox exceptions and diagnostics.
• What is search hijacking?Unauthorized browser-setting behavior.

Apple Safari

• Change your home page in Safari on MacHomepage and new-window behavior.
• Change General settings in Safari on MacEmpty Page, Start Page, Homepage, and session controls.
• Block popups in SafariOfficial site-specific popup guidance.
• Stop pop-up ads and adware in SafariApple's guidance for persistent unwanted windows and software.

How to use this library

Browser interfaces can change before this site is updated. When a menu label differs, the browser maker's current help page takes precedence. See our editorial method for the verification and correction policy.