Even still, there are quick and easy configuration files available online for software like i3 (https://github.com/minad/i3-config/blob/master/autostart) to make them compatible with normal Linux setups.
I don't know why Linux versions of browsers don't do this, but it certainly isn't a technical limitation.
Shh! Don't tell them! They might start doing it.
You absolutely can, there's ways for apps to launch without adding a dock icon or windows, this is typically done by menu bar apps, but can also be done by daemon-style services, or by apps meant to do global-style UIs (like a lot of the spotlight replacement apps)
Pluginitis sufferers, however, have very little insight into their condition and frequently react violently when you tell them that your browser starts in just a few seconds.
Back in 1999 my relatives were browsing the web over dialup with 640x480 screens and frequently had more than 50% of the vertical screen area consumer by window chrome, browser buttons, and toolbar after toolbar installed by multiple (now forgotten) web sites such as Yahoo, Lycos, Hotmail, AOL, CNET, etc…. Oddly none of these people saw anything wrong with this.
You're lucky. That's not my experience at all. I stopped using Firefox in part because it's the only browser that takes more than 2 minutes to start up on my Linux boxes.
It's true that I don't use SSDs. It's also true that no other app (including other browsers) takes such an absurdly long time to start up, so I don't think the lack of an SSD is the issue.
Or, if it is, that means there's a larger problem with Firefox. You shouldn't have to run special hardware to run a browser.
It's part of why laptops can't hold a charge anymore.
Not on Linux, which is what the parent poster is using. This "shut down means hibernate, you have to press restart to actually shut down" behavior is a Windows-only novelty.
For years, I've been using my laptops connected to external monitors and I/O devices with the lid closed. I've never had any of them get anywhere near hot enough to damage the screen.
I wouldn't be so quick to blame that on Linux as much as it seems there was a hardware fault in the laptop.
The only time my windows computer reboots is when the power goes out.
(Also, I highly recommend staying away from windows, Microsoft is getting incredibly intrusive. If my work didn't use windows exclusively, I'd be on linux)