Microsoft was slowly losing browser share with their own engine, felt they needed more web compatibility (including de facto via the WebKit lineage) and extensions sooner. They were not going to play a long game, even if they could afford it. Mozilla may have looked wobbly to them, too.

Didn't see your reply before this, sorry.

I hear what you're saying – but! – a tech giant has to play the long game. The Web is an open (for now) platform and Microsoft, like Apple, like Google, need to have their own web client/server implementation. Makes no sense to be beholden to Google imho.

I'm stunned at how little desktop browser share Edge has (4.6%): https://gs.statcounter.com/browser-market-share/desktop/worl... – however, changing browser engine is not going to change that, is it? I suppose, if Google and Microsoft end up equally and democratically sharing Chromium development then all's well.

Given the recent layoffs at Mozilla it's a pity (in hindsight – for the benefit of the open web) Microsoft didn't back them :(

Anyhow, thanks for the response.

Surely Microsoft has done their homework: researched everything and weigh the pros & cons. This is a big thing and the next step in their browser strategy. We can only guess their reasons, but clearly in their eyes, Chromium codebase is the better choice.

True, but big companies can sometimes make big mistakes, no?