If you start to re-order items in the Spaces Tree view by dragging the handle that appears to the left of the item:

then the first time you move an item in that folder, it will pop up to the top of the list instead of wherever you wanted it to go:

Fortunately, after that, moving that same item - or any other item in that folder it would seem, will actually leave it in the proper order.
I assume this is because this "re-ordering" is happening via metadata being stored in the SQLlite database and not actually in the notes or frontmatter anywhere, and the first time you try to reorder it will add that folder to the database but not actually properly record the data of what got moved to what position until the second time you attempt a re-ordering, at which poiint, the placeholder is already in the database so it doesn't hiccup trying to create the new data AND set the value(s) at the same time.
Occasionally - though I can't re-create it - an item will become stuck at the top and no amount of dragging to re-order will get it to appear any lower than the top. Not even trying to drag something else above it. If I can reliably re-create this bug, I will update this github issue.
If you start to re-order items in the Spaces Tree view by dragging the handle that appears to the left of the item:

then the first time you move an item in that folder, it will pop up to the top of the list instead of wherever you wanted it to go:

Fortunately, after that, moving that same item - or any other item in that folder it would seem, will actually leave it in the proper order.
I assume this is because this "re-ordering" is happening via metadata being stored in the SQLlite database and not actually in the notes or frontmatter anywhere, and the first time you try to reorder it will add that folder to the database but not actually properly record the data of what got moved to what position until the second time you attempt a re-ordering, at which poiint, the placeholder is already in the database so it doesn't hiccup trying to create the new data AND set the value(s) at the same time.
Occasionally - though I can't re-create it - an item will become stuck at the top and no amount of dragging to re-order will get it to appear any lower than the top. Not even trying to drag something else above it. If I can reliably re-create this bug, I will update this github issue.