gnome classic terminal mouse double click selection

For gnome-terminal:

In the menu bar, under Edit : Profile Preferences, tab General you will find Select-by-word chatacters. If you want the terminal to consider / to be a word boundary for selection purposes, remove / from the list of characters.

In some cases gnome-terminal preferences doesn't have the select-by-word characters option. It still has the profile-ID you need for command-line configuration though: Obtain it in the edit -> profile preferences -> General tab on your profile.

use

dconf list /org/gnome/terminal/legacy/profiles:/:b1dcc9dd-5262-4d8d-a863-c897e6d979b9/

to check whether it works. If no output, then the profile-id is not b1dcc9dd-5262-4d8d-a863-c897e6d979b9, copy pate the one from the preferences as descibed above.

then use:

dconf write /org/gnome/terminal/legacy/profiles:/:b1dcc9dd-5262-4d8d-a863-c897e6d979b9/word-char-exceptions '@ms "-,.;?%&#_+@~·:$"'

with the correct profile-ID. Here I remove / and = from the list but add $ according to the OP's wish.

Note that you can still select a word which is split by this character, say iceweasel/stable : double-click on the first part, then hold the shift key and click on the second part.