I'm having some problems with the MATE and Plasma .ISOs. I filed a bug report for the MATE .ISO, and I'll report one for Plasma, too, if I find out that I can't refer to one I've already created. The bugs are identical.

In preparation for creating a VM, I create a 32 GB virtual disk drive, and partition it like so:

I need a boot partition in order to do an efi-type boot, and a swap partition large enough for me to hibernate the VM.

With a disk like this, and choosing to use these partitions to install the OS, I had no trouble at all installing Budgie and GNOME. On MATE and Plasma, however, the boot partition was not recognized and a bootloader couldn't be installed there.

In the installers, the partitions are assigned to mount points, after choosing to use those partitions, their mount points are chosen on the next page. The swap and root partitions can be assigned to the swap and / mount points, but there is no mount point available for the boot partition. It's used according to its FAT32 format and (with GParted) the boot and esp flags that are set.

During the MATE and Plasma installations, on the next page, an error message is displayed, saying that a location can't be found for a bootloader, and one must be provided for an efi iinstallation. There's no way to continue. I've double-checked that the disks are created properly, as in the above image, and as a reminder, the Budgie and GNOME installations worked correctly.

Any advice from the team?

    WetGeek Since you already created an issue on the issue tracker (here, for anyone else that wants to follow along), I would say to watch that for responses. People may have additional questions or thoughts, and it would be good to have that all in one place. Also, if the same issue appears on another edition, you can just add that to the current issue. No need to create a separate one, I would say.

    Also, thank you for filing issues on the tracker, that's exactly what we're looking for! 🙂

      WetGeek an error message is displayed, saying that a location can't be found for a bootloader, and one must be provided for an efi iinstallation

      I plan to continue by allowing the installer to partition the disk, but that will leave me with BIOS-based VMs that can't be hibernated, which is not my customary workflow. I'll need to create new ones if/when this bug is fixed.

        I'm going to abandon the MATE .ISO and try to install the Plasma edition. With MATE, I deleted the partitions I'd created, and let the installer create its own. That seemed to work fine. The bootloader was installed. The next page is shown here:

        That's correctly filled in, my password and confirmation field match, and yet the [+Add now] button and the [Next] button remain disabled, so I can go no farther with it. With a new installer planned, I'll look forward to trying that.

          WetGeek The icons indicate a problem with the username. Is there an extra space at the end, by accident?

              @EbonJaeger : Looking at this page again, I notice a different symbol after the line with my user name. Before, I'd only checked the fields to be sure that my user name and the confirmation field agree, which they did here.

              I don't know what could be wrong with "jerry" as a user name. It's what I've always used.

              I noticed that Swap Usage in Usage Monitor Raven widget is activated after the last or previous update(s). I am pretty sure I disabled it before.

              EbonJaeger Is there an extra space at the end, by accident?

              I'll check it. These text fields should be trimmed in the code to prevent that from happening.

              EDIT: Yes, that was it, one space at the end. It's now installing. Thanks for suggesting that.

                I've created four VMs to test the 4.4.ISO files, and I've configured the Plasma VM to be a useful daily driver.

                • Launched Konsole and tried an eopkg UP, but as expected, there were no upgrades available.

                • Installed packages I'd need - nfs-utils, micro editor, Vivaldi-stable, aisleriot, kshisen, gnome-mahjongg.

                • Launched System Settings and adjusted the ones that dim or turn off the screen, and created 8 virtual
                  desktops. Also checked the option to start each session as an continuation of the previous one. That used to
                  be the deault, but it's not in this version.

                • Accessed my LAN from Dolphin and fetched my bashrcAdditions file and the shares to add to /etc/fstab.

                • In Konsole, I added bashrcAdditions to my home folder, and source statements in .bashrc to reference it.

                • In Konsole, I addedthe extensions to /etc/fstab to access my NAS shares.

                • In my home directory, I deleted all the folders, except Desktop, and replaced them with symlinks to my NAS.

                • Configured Vivaldi, to include installing LastPass and doing a sync (results in image, above).

                • Configured Thunderbird with email accounts for Jerry and Wetgeek.

                • Launched and configured the three solitaire games -- Spider, Shisen-sho, and Mahjongg.

                  Note to @EbonJaeger: I plan on configuring this VM farther (address books and calendars in Thunderbird, named tab stacks in Vivaldi, etc.) but I want to get all the VMs up to this point first. Also, do we have a specific place to document what we've tested, or just put it here?

                In this setup and configuration, I've run into no errors of any kind, so nothing to log in the dev tracker.

                  The second testing VM I've configured today is Budgie. Since I'm making the initial configurations the same for all four editions, I won't detail what I've tested here -- the list would be the same as in the Plasma message above.

                  I'll point out, for Budgie, that the Nemo file manager looks and works great. It accepts my choice of a dark theme with no problem, and the folders, except for Desktop, are linked to shares from my NAS.

                  As with the Plasma VM, I encountered no errors during any part of this installation and configuration. Congrats to the team!

                  WetGeek Also, do we have a specific place to document what we've tested, or just put it here?

                  `I would say to put testing stuff in the dedicated Solus 4.4 ISO task. Makes it easier to keep track of what's been tested and what hasn't.

                      EbonJaeger I would say to put testing stuff in the dedicated Solus 4.4 ISO.

                      So, just open up the .ISO with ark and put a file in it? A text file would probably be easiest, but least readable, especially with no formatting. How about a LibreOffice document?

                          I guess I don't need to tell all y'all that this is my GNOME VM. It's pretty ... uh ... distinctive, I would say. As with the Plasma and Budgie VMs, this is minimally configured as a daily driver. I'll add more configuration in time, but I want to get MATE to this level first.

                          More congratulations are due to the dev team. I encountered no errors during setting up and configuring this VM.

                          Finally, here's the MATE testing VM, such as it is. Solus MATE has always been the most difficult DE for me to work with, and as such, this isn't configured exactly like the other three editions, but it's close. I couldn't access my NAS via Caja, and I couldn't connect with the USB drive plugged in to the host, so I was unable to modify /etc/fstab to access my NAS shares, and thus replace the home directory's folders with NAS shares, as I did in the other VMs.

                          But Vivaldi, Thunderbird, Spider sollitaire, Shisen-sho, and Mahgongg are all installed and configured, as on the other VMs. There are several virtual desktops displayed in the bottom panel that are represented by rectangles instead of application icons. In fact, the only ones with icons are Thunderbird, Vivaldi, and the MATE terminal. I think I've noticed this lack of icons before, but I'm not positive. If someone with more experience using MATE has an opinion on that, I'd defer to that person.

                          Since I started with Solus, I've used mostly Budgie and Plasma personally, so I'm less familiar with the other DEs. At any rate, this VM will make it possible for me to verify fixes and try new features, so it should serve its purpose.

                            WetGeek I dont use Nas at this point in time but its on my list when I get my server set up
                            but I have never had a problem with anything usb on Mate. (I find it very strange)
                            And I dont use Desktops either (Never had any icon issues in general)
                            So my comments are limited with respect to your issues
                            I think mate is lagging somewhat because a need for maintaner I hope its life isnt limited.
                            Myself I just dont have issues with it Does everything I want.

                                Axios but I have never had a problem with anything usb on Mate. (I find it very strange)

                                yep. I find the theming rectangles very strange after the usb.

                                WetGeek Solus MATE has always been the most difficult DE for me to work with

                                I always found it the easiest. but like axios said I have no NAS. Caja otherwise picked up all drives.
                                Gnome is gnome-y, plasma has 684 settings where it needs about 200, budgie easier than both but can get cantankerous...but Mate is so perfect it's boring. I can't wreck it. It's lets me operate it.

                                I often wonder if the VM doesn't add layers of differences in some way? I mean, OOTB with rectangles instead of icons in workspace thumbs is not something I'm familiar with. Seems a lost in translation thing.
                                That said, you are testing so it's all valuable.

                                      Axios Myself I just dont have issues with it Does everything I want.

                                      Obviously you and I are trying to use the OS differently. I'm very happy that it works well for your needs. And keep in mind that I don't have anything against MATE, it's just that Budgie, Gnome, and Plasma will all connect with my NAS using the smb protocol (Samba) that lets Linux machines talk with Windows machines remotely. Smb is how Windows servers talk with each other, and with the workstations in a workplace.

                                      All I need to do is click on the Network link in that DE's file manager. It even works for distros that I can't get to connect using the Linux native nfs protocol. (My NAS supports both, so in a mixed workplace, it can support Windows and Linux computers.) But why is a NAS so important to some folks, like me, for instance?

                                      My NAS (network attached storage) is important to me, because it holds family pictures, music, movies, documents, downloads, source repositories, ebooks, backups, and more -- that I've collected over decades. It's a little Linux server in a case with four huge disks (10 TB each) in a RAID array. At this point, it's about half full. It communicates with every machine here (hardware and virtual), so that they don't need to store all that data themselves.

                                      And that happens to be where some of the software I use to configure systems resides, So when I create a VM, or when I buy a new computer, it's important for me to be able to connect it with my NAS. Not everyone needs to be able to do that, but I do. And when a system makes it difficult or impossible to do that, I say so.

                                      And with Budgie, GNOME, and Plasma VM's, I can share certain resources with the host machine the VM is running on, like the clipboard, files, or USB ports. I keep a set of files that I use to configure a new machine on a USB drive. I did that originally so that I could set up identical classroom computers without the need for a network, but I've also found it useful even outside of the classroom.

                                      With Budgie, GNOME, and Plasma VMs, their file managers will automatically mount a USB drive that I've inserted in a port on the host machine. It's a feature of VirtualBox VMs, but MATE doesn't take advantage of it. At least not that I've found so far. It's the TRANSFERS that's mounted in the file manager, like in this shot of Nemo in my Budgie VM.

                                      The issue of the rectangles instead of application icons in the display of virtual desktops is an interesting one. Plasma, for example, displays, by default, empty rectangles that show the approximate size and shape of the windows running on that desktop. But if you right-click on one of them and choose to configure the Workspace Switcher widget (a.k.a. Pager), the first setting in the list is the one that displays application icons instead. Some DEs, like MATE, don't have that setting, but simply display the application icons all the time -- or rather, sometimes. As you can see, it appears to be selective in MATE's case, as some apps appear as rectangles and others show up as icons. The rest of the applications that appear as icons in other DEs just show up as the rectangles I mentioned. Here's a better look at them.

                                      From left to right, these represent Thunderbird, Vivaldi, Spider solitaire, Shisen-sho, Mahjongg, Settings, Caja, and the MATE terminal. I don't know why the terminal displayed as an icon yesterday, but not today. Thunderbird and Vivaldi are apps that I installed from the repository using eopkg, but so are Spider, Shisen-sho, and Mahjongg. The others are native to MATE. So I don't know how it decides to display icons for some and outlines for the others.

                                      This has been a long message, but I wanted to explain why I mention whether a distro supports a NAS, or its DE works in ways that work for me. As I said in the beginning, I have nothing at all against MATE, if it does everything its user wants and needs. I could even live with it if I had to. But with Solus, I don't have to. Also, I hope it's clear why I appreciate a distro or DE that makes it easy for me to access my NAS, whether by smb or nfs. And I love that many will work with VirtualBox so that a VM can access its host's resources.

                                      My goal yesterday was to get four Solus .ISO files installed on VMs, and minimally configured as a useful daily driver. I'll likely be using them differently over the coming days, and I'll certainly be doing more configuration. Maybe if I install the VirtualBox guest additions for the MATE DE, it will be able to access more of the host's resources, for example. I haven't needed to do that with any of the other DEs.

                                          Has anyone using VirtualBox tried to install the guest additiion into a VM, and been told that they can't be found, and asked, would you like to download them from the internet?

                                          And then, when you try to do that, you get this error?

                                          This used to work for me, but recently it hasn't. Before, I'd just tell the host to insert the image file, and it would happen. Some time later, I'd need to grab it from the Internet, but that worked without an erorr. Now I can do neither. It's something I rarely need to do, so it doesn't affect me much, but I believe I have all the VirtualBox packages I need on my host machine, and can't understand either of these errors. I don't understand why the host can't just insert them, and if it can't, why I get a useless error message when I try to fetch them from online.

                                          Today, I'm trying to install the guest additions into a MATE VM, but so far I've failed at that. I can report it as a bug in the Dev Tracker, but I'm reluctant to do that if it could just be something amiss on my laptop. That's why I'm wondering if it happens to anyone else.

                                            WetGeek I was curious on desktops appears its the same as mine

                                            The blue are programs open but icons dont show up and the last grey one not used (Interesting)
                                            You are right about it. (I cant say if this is normal or not)

                                            Any usb drive I ever had always popped up a Icon on desktop for it.(You may have to turn it on under mate tweak
                                            dont remb what the default was,but still should show in file manager)
                                            They have guest additions in repo.

                                            I wasnt getting defensive about mate its good to know these things
                                            Will be setting up nas on dell server so will find out about that stuff this winter, If it dont work for me
                                            I will have to go to budgie or plasma I guess.
                                            Seen they did some fixes to samba in new iso but dont know about that.