yup. either works. also clicking a second time puts the text input cursor at the site of the last click. click fast enough for a 'double click' will select the word or whatever windows thinks is a 'word' nearest to the double click.
also F6 or CTRL-L will put the focus up there without having to click. saving the mouse from making the (potentially long) journey there. then END or RIGHT puts the mouse at the end of the address. a programmable keyboard or utility, or autohotkey, could be used to make a new custom shortcut that hits those two keys with one keypress or alternate mouse button click.
the reason for the default behaviour is because the most common (and overwhelmingly so) things people do when they click or give focus to the urlbar is either copy its contents to the clipboard, or replace it entirely by pasting or immediately typing. these things require the entire url address to be selected upon focus.
That it didn't select everything was only the default on Linux, to accomodate the folks using the middle-click clipboard (primary selection).
But yeah, I don't remember, if there was a good reason why they removed it. I think, they replaced the URL bar implementation and just have this feature in the new one. So, maybe they'd accept a PR?
My understanding was, addons (the new versions we use now) were not allowed to clear the address bar. At least that was the excuse they kept pushing, so they removed the setting.
to accomodate the folks using the middle-click clipboard (primary selection).
That rather understates the insult that the current behaviour is to Linux users. There was not a good reason for removing the option to have it work properly, which was available for many years. The reason given was entirely nonsensical. But no, they will not accept a PR. It was a contentious issue and opinions were hardened in the flame wars that followed.