Chrome, Firefox, and Edge are about to hit version 100, in a triple release that could break some websites. The move to version 100 in the coming weeks could result in bugs or compatibility issues on some websites not ready to read triple-digit user-agent strings. Google, Mozilla, and Microsoft are busy trying preempt any big issues.
Mozilla, Google, and Microsoft have been warning about the upcoming version 100 release for months, which is about to drop in March for both Chrome and Edge, followed by Firefox in May. Mozilla and Google have both been running experiments to test websites and report breakages. There’s a running list of issues, which is fairly small right now, and Engadget notes that the notable sites affected include HBO Go, Bethesda, and Yahoo.
“When browsers first reached version 10 a little over 12 years ago, many issues were discovered with User-Agent parsing libraries as the major version number went from one digit to two,” explains a team of web developers in a Mozilla blog. Much like the infamous Y2K bug that made the year 2000 indistinguishable from 1900 for some computers, browsers have different formats for user-agent strings, and “it’s possible that some parsing libraries may have hard-coded assumptions or bugs that don’t take into account three-digit major version numbers.”