Not a problem but just some feedback. When you click on one of the icons in the left vertical panel after it has been selected it collapses the panel next to it but there is no indication that the panel exists after that. It just disappears. The only indication that the panel is there is if you mouse over the line between the panel and the main panel the pointer changes to a double arrow and you can drag it open.
The kebab menu on the "database" panel only has one option under it "Drop database" but you have no way to know what's under there other than to click on it to see what's there. It seems like it would be better to just replace the kabab menu with "Drop database"
The menu on the lower right of the main panel in "Workspace" and "Virtual Graphs" gives a menu with "sparql, txt, turtle, srs...etc" but doesn't really give any indication about what it's doing. It seems to be selecting what type of thing you're working on in the workspace and can be set on a per tab basis. i.e you can select sparql for tab 1 and json for tab2 but that's not apparent because it's in the light blue bar that spans the entire window past the tab not in the tab panel itself. I'm not sure how you'd use type text. Maybe if you wanted to write some notes?
I found the "Database" section a tad confusion at first. I kept wanting to be able to select "databas" and then query not select workspace and then select the database. It felt like if it was labeled "Database config" I wouldn't have felt that way. The "load data" button in the "database" section felt a bit out of place. Without that the database section is all configuration and all datatabase content manipulation would be done in the workspace. Perhaps that button might be better in the worspace.
There seems to be a lot of selecting the database in general. The workspace tab, searching stored queries. It felt like if you had put workspaces under the "database" section you could select the database once and be done. I guess that depends on your work flow and if you're bouncing around a lot of different databases.
Hopefully my descriptions make sense. Again, this is just my personal impressions and might not be shared by others but hopefully it helps.