MHTML in Chromium

The MHTML file format (aka “Webpage, single file”) allows a single file to contain the multiple resources that are used to load a webpage (script, css, images, etc). Edge (Chromium) has an option to use the format when saving the current page via Ctrl+S or the Save page as… menu command: … but the browser’sContinue reading “MHTML in Chromium”

Download Blocking by File Type

Last Updated: 20 May 2024 I’ve previously gushed about the magic of the File Type Policies component — a mechanism that allows files to be classified by their level of “dangerousness”, such that harmless files (e.g. .txt files) can be downloaded freely, whilst potentially-dangerous files (e.g. .dll files) are subjected to a higher degree ofContinue reading “Download Blocking by File Type”

Per-Site Permissions in Edge

Last year, I wrote about how the new Microsoft Edge browser mostly ignores Security Zones (except in very rare circumstances) to configure security and permissions decisions. Instead, in Chromium per-site permissions are controlled by settings and policies expressed using a simple syntax with limited wildcarding support. Settings Page’s Site Permissions and Group Policy Internet ExplorerContinue reading “Per-Site Permissions in Edge”

window.close() Restrictions

Sometimes, Web Developers are surprised to find that the window.close() API doesn’t always close the browser window. When looking at the Developer Tools console, they’ll see a message like: Scripts may close only the windows that were opened by them. Why Do Browsers Limit close()? Before we dive into what factors govern what happens whenContinue reading “window.close() Restrictions”