You assume that "side projects" are taking up a substantial proportion of development resources. They really, really aren't. Experimental projects are mainly small groups exploring possibilities. Initially 1-2 people, growing when (and if) they seem to be getting somewhere. At various points in the history of the project, it's been more developers vs product people who come up with the initial ideas.
The rest of us are working on stuff like: Fission (process-per-tab, roughly). Pageload performance. Memory usage. Printing. Moving stuff to the GPU. The never-ending treadmill of new web APIs. Porting to new platforms. Fixing bugs.
As for extensions: there is no intention to regain 100% of the power of XUL extensions. Never has been. Many extensions used to get the source code of an internal function, search and replace to update the code, and reinstall it. We're not going to return to that level of power. (Yes, XUL extensions don't have to do it this way; I'm using an extreme example to illustrate the former power.)
But that's not to say that Mozilla doesn't want to increase the power of WebExtensions. I'm not really privy to the decisionmaking there, but look -- we just laid off 250 people. I hope that's adequate proof that we have to make some hard resourcing decisions. And most of the "why don't you just..." requests are not as trivial as they seem, even when the requester's exact use case would be fine. Any extension API that allows deceiving the user or subverting their intentions must be handled carefully to maintain the security of users, and people are pretty darn good at finding unexpected ways to exploit seemingly innocuous capabilities.
I'm not going to debate the history or correctness of all the decisions that bother people. I agree with some, disagree with some, and aligning my views with yours or anyone else's isn't going to have much of an effect on anything. We've screwed up. I'm sure we haven't properly admitted to some screwups. People's experiences and workflows are different, and I know I'm always surprised to discover that 99% of users are not seeing something that bothers me. My intuition of what is or isn't important is not as good as I expect it to be.
The rest of us are working on stuff like: Fission (process-per-tab, roughly). Pageload performance. Memory usage. Printing. Moving stuff to the GPU. The never-ending treadmill of new web APIs. Porting to new platforms. Fixing bugs.
As for extensions: there is no intention to regain 100% of the power of XUL extensions. Never has been. Many extensions used to get the source code of an internal function, search and replace to update the code, and reinstall it. We're not going to return to that level of power. (Yes, XUL extensions don't have to do it this way; I'm using an extreme example to illustrate the former power.)
But that's not to say that Mozilla doesn't want to increase the power of WebExtensions. I'm not really privy to the decisionmaking there, but look -- we just laid off 250 people. I hope that's adequate proof that we have to make some hard resourcing decisions. And most of the "why don't you just..." requests are not as trivial as they seem, even when the requester's exact use case would be fine. Any extension API that allows deceiving the user or subverting their intentions must be handled carefully to maintain the security of users, and people are pretty darn good at finding unexpected ways to exploit seemingly innocuous capabilities.
I'm not going to debate the history or correctness of all the decisions that bother people. I agree with some, disagree with some, and aligning my views with yours or anyone else's isn't going to have much of an effect on anything. We've screwed up. I'm sure we haven't properly admitted to some screwups. People's experiences and workflows are different, and I know I'm always surprised to discover that 99% of users are not seeing something that bothers me. My intuition of what is or isn't important is not as good as I expect it to be.