There are many Linux distributions including this amazing one Zorin OS and each one may have something we may love. It could be something as little as 'Sound Intro', Notification panel, Icons, Cursor etc. We can't install all of them, so Gnome Extensions help us make our system look just like the system we want, could have had or would like to have.
I install all my extensions through https://extensions.gnome.org/ because there are user reviews which sort of predict what you may or may not get in an extension. Many users when they're satisfied with an extension will leave a review and likewise if they are disappointed they will also drop a clue. I have tried the snap apps like Extension Manager that can list them for you within the app, but I notice you can't scroll down, you can only browse the selection they present.
Gnome website is also useful because there are some stubborn gnome extensions. They can be removed and toggled as soon as you encounter glitches and issues, you can one-click install, and you can leave a rating and also file a bug which you can't do otherwise in other apps.
For example, I installed a clock on my desktop and as soon as I did my Wi-Fi connection disappeared, guess what I did next? Remove extension and log out, then log in. Back in business.
Thank you Harvey, this has been an issue for me especially with funny extensions that affect how other extensions work. What is KDE please and how will I impliment this with Zorin?
KDE can be nice if probably set up (which can takes hours if you don't have a clue to do so). We'll have to see what the Zorin brothers are going to do before I move away from Gnome when that time comes. I like Gnome cleanness compared though.
I actually pay zero attention to reviews, I don't leave them good or bad, those reviews are highly outdated, and most importantly you have no idea what system they're running. Plus you have no idea the person leaving the review, it could be the dev himself leaving good reviews even though the extension doesn't work. Reviews IMO are completely useless and should not be a gauge by which you install things.
I agree with @337harvey that it makes no sense to have to install basic functions that other DE's have by default. It's just one of many reasons I do not like nor use Gnome. I use Cinnamon, but used KDE for years. Plus Gnome devs seem to go out of their way to break those extensions. The question was posed, then what? Then what indeed.
You should really read up first, you can search this forum, then try other DE's.
I started on Gnome, using Zorin OS. I struggled and struggled with it. Gnome is so much like Microsoft, I nearly went back to Windows several times. It seemed pointless to use Linux.
Got a lucky break when I tried out Zorin OS Lite and the struggles and troubleshooting reduced almost to a full stop.
Sadly, Gnome controls GTK, which many desktops still rely on. So Gnome is influencing all other D.E.'s other than KDE which uses QT. QT was introduced years ago as a resistance to what the Gnome Devs are doing.
I just noticed that there's a Wayland update to Zorin. It's really not bad, one thing I appreciate about Gnome is the ability to run custom themes. I will check Wayland out this week and compare. Keep it light, not too much info in the mail you use for account sync.
You can run custom themes on the other DE's as well, it's not unique to Gnome. Nothing Gnome does is all that unique, or special. What is unique to Gnome is their dev's ability to get people to leave and their ability to remove basic functions.
I really really suggest you try out other DE's, so that you have a better perspective. But many of us here know what the DE's are and what they do, which is why so many of us choose to use something other than Gnome.
Yes, as I previously stated. You can make all kinds of changes as well...
Gnome is not special or unique, all the other DE's can make changes and more. That's why I suggested you actually read up on the various DE's and try them out.
It just gets the most hits. Many other D.E. themes will show up appearing to be the most if you annotate them:
xfce-look
kde-look
gnome-look...
Cinnamon themes are also kept on Cinnamon Spices, not really on Pling ("D.E."-look pages).
Gnome does have many themes available, many of which look mostly alike, to me. The colors change.
However, in brutal honesty, Gnome is the least theme customizable. Gnome has removed a large number of widgets and features. It also removed a lot of user customizations - which many search terms you run will show the history of.
XFCE, KDE and LXDE / LXQT take top digs on user customizability.
Cinnamon takes second place.
Gnome is last.
It also has more to do with what you can customize widget-wise than what pre-made themes are out there.