@Aravisian, @Frog, @SignorCastello and @zabadabadoo, let's chat about computer cleaning separately from Uninstalling preinstalled applications. I see that BleachBit has a simple interface, similar to Wise software I used on Window, and Stacer adds network monitoring feature that's another thing that I was looking for to save a history of used connection since on my connection monitoring webpage I only see the current and monthly usage, never a history. While I'd like BleachBit for its simple interface I'd exclude it since zabadabadoo pointed out that it runs clean up commands behind the scenes, and if it's not editable by the user I can't use it otherwise it will delete dependencies or packages that other software use. To make it simpler, here are my preferences for a system cleaning software:
no “invasive” cleaning, like cleaning something secretly without my consent
safe cleaning, for example of screenshots previews and thumbnails files and cache that recreates itself
uninstallations residuals removal, without removing dependencies and packages automatically
fairly simple GUI, if possible
complete scan for both uninstallations residuals and files that are safe to remove
warning before removing stuff in case it's shared with other software or system processes or it's anyway critical for stability, if possible
I think Stacer is good because you can expand different categories of items to be cleaned to make sure you don't get rid of stuff you don't want removing.
BleachBit fits this bill neatly. Everything that it will clean - is a checkbox. And, it has clear descriptions in the right pane of what it all means.
There is no invasive cleaning done in secret. Zero.
The GUI is reasonably simple, though it is more complex than UbuntuCleaner. It is equal to Sweeper.
I do not know of any app that can do this in an intelligent and automated way.
That is because an app cannot make a determination as to what is safe to go and what is necessary to keep. But you can.
You see, you know whether or not you are likely to reinstall an application and need its config files in the future.
So, in your Home Directory, look through ~/.config and ~/.local/share and you can choose to remove any folder that is for an application you know is Gone For Good.
And this is the most important tip:
Do Not Stress It.
If you are unsure... Leave It. It's ok. Many of these config files that remain behind are in the size range of 10's of Bytes to maybe 500 bytes in size. Which on a half-terabyte drive, is approximately 0.00000000005% of your available space.
Is that really worth sweaty palms over?
Users can easily get carried away with cleaning and it often is on par with them trying to clean their living room carpet with tweezers.
I'd like to go against @Aravisian only because Luca asked for a friendly GUI.
I'd recommend Ubuntu Cleaner instead of Bleachbit for the above motivation.
@Turtle11, looks like Sweeper deletes what the basic Zorin OS Core can already delete by default, from Settings > Privacy > File History & Trash Bin. The only addition is probably the feature to remove thumbnails files. Then I clean my browser stuff manually, because some cookies and temporary files have data that I want to keep. Also, some cleaning features are aimed to KDE and I don't have it, not yet for now. @swarfendor437, I tried Stacer and it's weird that misses of network usage history save feature seeing that has many other features. I couldn't even send a feedback, it was always failing 
. For network usage history save I may use Trippy but has a weird and probably complex GUI.
zabadabadoo said that it runs clean up commands behind the scenes, are you sure it doesn't delete stuff without my consent and knowledge?
It's fine, in fact I said without removing dependencies and packages automatically, I want to choose which to delete manually.
Yes, I know that most of them are tiny. I just can't stand leaving uninstallation residuals. Obviously I don't remove folders with names or part of names of deleted software unless I am sure that they are actually residuals of them. Now I go, I have to clean my bedroom with tweezers 
.
@SignorCastello, from BleachBit screenshot looks like it's structured like Wise Disk Cleaner and other WiseCleaner software that I was using with Windows, so simple lists with checkboxes, nothing too complex for my eyes.
I am 100% sure. I can say this with a Lot Of Confidence because I actually have reviewed the open source code for Bleachbit and even offered a small correction to it here:
What @zabadabadoo was referring to was that it runs the same commands that you would run in terminal behind that GUI screen. Not that it runs commands "behind your back" when you are not actively using the application.
BleachBit is not automated and it will not run at all unless you launch it and operate it.
It does not run in the background. When you close it - it fully closes and kills the process. So if you launch it again after closing it, it must fully initialize.
You placed that post on Customization 
?
It fits the bill...
?I customized BleachBit to accomodate themes properly on Zorin OS?
So, it's perfect, caro Luca. I love Bleachbit by myself!
I installed BleachBit and I'm going to try its cleanings progressively, there are so many options. Looks like it detects the installed software and loads its own section with cleaning options to choose according to the superfluous file types that the software can generate, right?
right.
@Luca_Pavan if you want to remove the unnecessary files on root (I highly recommend you to do that)
press ALT + F2 and write there pkexec bleachbit
I'm not so sure now that I viewed the whole list, I see entries for software that I never installed, like Nexuiz by AlienTrap Games, Opera, Pale Moon, Skype and Zoom, plus many more. I don't like that developers add stuff assuming that the user has it, like bloating phones with Instagram, TikTok, Facebook, Snapchat, YouTube and other stuff assuming that the user use it like a standard.
You mean for automatic cleaning at startup? Anyway I prefer to clean my computers manually, just to see what's going to delete.
Those are just entries for cleaning those files if they exist - not entries for preinstalled applications.
In my app menu, when I pull up BleachBit, there are two launch options: BleachBit and BleachBit as Root.
In mine too, but I thought that on gnome this wouldn't be the same.
At the beginning BleachBit would have about 200 entries, considering that 90% of them are software that I don't have at all.
Luckily enabling
Hide irrelevant cleaners on Preferences I reduced the list to only 7.
Then the progress bar is faulty, it's at
Done. (Fatto.) despite its appearance shows a running process that doesn't really exist. However, a Discord cleaning makes Discord lose my verification so I have to register again but I see no Password or anything related to authentication or user profile entries for it. Moreover, BleachBit is unable to locate uninstallations residuals, I opened /home/.var/.app and found 2 files myself. Of course there are many more scattered around.
Which computer cleaner to install?
None - To dangerous if you do not know what you're doing. It should only be used by people who actually knows what they are doing. It's easy to brick your system with these apps.
@catlikehana, I see that your command updates and upgrades but I don't want to do both automatically since there are some updates that I don't download and I don't want to update yet for safety. @Storm, I know, but I have enough experience to know which options to check to the cleanings and which not since when I was using Windows I used much WiseCleaner software that clean the cache, delete thumbnails files and any other stuff that BleachBit does, but I see that BleachBit hasn't 1 thing that I wanted. Probably the only way to brick a Linux distro is when these apps remove critical configuration files or dependencies, or part of them, but usually these apps aren't mean to delete such important stuff, they show a clear warning before proceeding or separate it in a section for advanced users. I see that BleachBit limits itself to common cache, thumbnails data, trash bin, clipboard and other harmless entries.