There are linux downloads of xampp here
but
generally in linux you look in your distro’s repository first, and only if it is not there do you go looking at sites like the above.
Linux is different from Windows in that respect. New linux users, from windows, tend to go looking all over the internet for software when they dont need to, because it is there as a package in their distros repo.
So, search your repo first.
apt search keyword
for Debian based distros.
I have downloaded XAMPP. No issues. But I have to upgrade the MariaDB. But there is no XAMPP add-on for Linux like it has for Windows and I couldn’t find any solution and this is the problem of Linux. It is a superb OS but you cannot do creative professional work in it. This is not the fault of Linux but of the developers because they are reluctant to make any serious app. Why? According to the developer/owner of ‘SHOTCUT’, Mr. Dan Dennedy, “since it is freely available, either it works for you on your system: you decide.” Here is the original link: Shotcut not using GPU & showing memory errors - #2 by shotcut - Bug - Shotcut Forum. I wrote a protest against his mentality and my reply was deleted.
If this be the general mentality of the Linux app developers, the hope for Linux to be a major alternative of Windows, is very far.
I know. 
And this is the second thing which made me love Linux. But, there are certain apps which are not included in the distro repository and it is very normal. There are so many apps out there and not every developer made a distro specific package. Instead they make a common package compatible to core Linux like XAMPP. They have all their products in Sourceforge repository and if you go there and go to the ‘FILES’ tab, you will see that there are add-ons for Windows but none for Linux except the main XAMPP app. These add-ons are the easiest way to change the versions of each and every product included in XAMPP and I know exactly why they haven’t made any Linux specific add-on. Because Linux has not been emerged as the biggest alternative of Windows. As per the present scenario, we can see that there are many distros are taking birth now and then. But in my opinion, if the developers thought and engaged in making Linux specific packages, then this scenario would change. But they failed to do so because the only behind-the-scene cause is MONEY. If they get at least the cost of their work, they would be encouraged and that’s why the FOSS initiative has to be evolved. The rule makers for the FOSS initiative, have to be PRACTICAL. An initiative cannot live without people and here the ‘PEOPLE’ means ‘DEVELOPERS’. FOSS management must understand that, otherwise there is no hope… at least I can’t see any.
I see your point.
There is some software that is not OS specific… you can run it in any environment but you may have to compile it. It is mainly numerical code that does not make system calls.
There are ways of putting a wrapper around things so that they are protected from the OS. One way is to put them in a docker container. I believe that something like Mariadb could be containerized so that it would run in any OS that supported docker containers. That sort of thing is probably the answer developers are looking for, as they would only have to port it once and supply mariadb as a docker image that any OS could install.
Does Win support docker? I have no idea.
There may even be a maria docker image already? I must look.
PS.
It looks like there are limitations to running a docker container on windows
The concept may yet still work with a bit of effort, or there may be some other sort of wrapper. A whole VM would work, but that is wasteful.
A docker image would run on any Linux distro… that is still a saving for developers.
There seem to be docker images for mariadbp
https://hub.docker.com/search?q=mariadb
That may help with your problem. The docker image version may contain the addon
There are 10,000 results! 
I cannot search this huge database and moreover most of their terminologies are going over my head. I am not a programme developer. I just need to upgrade or downgrade my MariaDB package version which comes with XAMPP. FYI, MariaDB is already installed but the version is higher than in my online server. I need the version 10.6O and I found the version in https://mariadb.org but my countries datacenter is failing. A 404 error… what a joke!!! But on second thought, it was not meant for XAMPP but made for Fedora itself. So, I don’t think it can be done easily in Linux that is upgrading the MariaDB version in XAMPP and I have to wait till XAMPP publish add-ons for Linux like it is doing for Windows. Till then I have to stay with Windows for work purpose. 
I think the Moderators should transfer the posts related to MariaDB to a new thread so that more members can share their opinions which would be beneficial to people like me who have just started their journey into Linux world and syruggling to find proper solutions.
I should thank you all who have tried to help me but I couldn’t figure it out due to my lack of knowledge.
What I haven’t mentioned earlier probably, I am using Thunderbird in Fedora 40 Workstation and I downloaded Thunderbird from their own repository because firstly, I prefer distro’s own repository and secondly, the Flatpack version was older. I am talking about pre-Nebula. Afterwards Firefox updated itself to Nebula and working fine. I think, KDE NEON is a bit behind in the race regarding some integrated apps. You can try Fedora and install KDE Plasma DE or there is also a Fedora-KDE Spin. You can try that too. In it you will enjoy all KDE flavours with Fedora’s stability with an arsenal of current vesrsion softwares.
Welcome to Linux. One of its characteristics is it forces you to learn in order to be able to do things. I admit, docker is a big learning curve. Maybe i should not have suggested it… but… containers is becoming more and more the way people work today… it is worth getting into.
I have to learn coding!!! Oh, nooooo… not again!!! 
I understand. But I have mouths to feed brother. After spending a hectic day, I got a little energy to start learning new things which has a steep learning curve. But, to some extent I have to learn Linux which I am doing and if I need some solutions, I have you all my friends to get answers. Haven’t I? You are my extended family. 
Yeah , you are in the wrong phase of life for big learning projects.
You need to be a bit code-savvy to use containers, but you dont do heaps of coding.
It is more like learning another package system.
I am not really a container expert, I have only done a bit of low level work with docker
building images…
There are high level ways to manage containers, and there are people here with experience at that.
Yeah! That’s for sure.
You are making me curious. I think, I should look into it.
Thank you for your convincing advice.
I cant even point to where to start. Find someone who actually uses containers in their daily work.
Don’t know if anyone else has this issue.
But, no matter which version installed, even if configured to do so, Thunderbird won’t remove deleted items on exit (something Outlook shareware version does quite well on Windows).
update: tested on Betterbird flatpak ed., and emptying trash on exit works.
I’ve been using BB (Flatpak) for some time now on Debian 12 and I’m well convinced that it is a better bird (sorry) than TB. Changing from TB to BB was made easier by using the export tool in TB and then importing back to BB.
Incidentally, I have both the .deb version of TB and the Flatpak BB co-existing on the same PC with no issue (so could always revert to TB if wished).
KDE Neon is based on Ubuntu 22.04 (from 2022) hence the older TB version. I’m not sure when KDE will update Neon to the latest LTS.
//
I’m running the Thunderbird Flatpak on Fedora with 3 IMAP accounts. She opens and closes normally for me. Admittedly, I only use it to look at my spam folders and to get info before Gmail POPs the mail out.
Are you running any extensions (addons)?
Actually, have been away from Thunderbird for a while.
Will respond maybe after this weekend.
Been busy painting stuff.
Downloaded and installed Thunderbird Nebula as Flatpak this past weekend on latest KDE Neon Plasma 6.2 and it works as expected.
Have only two extensions and one theme (just as before).
Why it works well now and not before is beyond me.
Anyhow, case solved!