Original fix was here #11571 this is a redo with testing instructions and without swearing.

To test

• with making the ordering inputs visible (and thus editable too)

Joomla backend articles manager,
featured manager,
and category manager

• Edit "styles" of isis template add file css/custom.css with:

.text-area-order, .sortable-handler + input {
  display: inline !important;
  width: 40px; text-align: right;
}

1. In e.g. feature manager make hard refresh to get new JS loaded and sort by the ordering the column
2. E.g. i have 10 records, manually (typing) reverse the last 4 items e.g. 7 - 8 - 9 - 10 to 10 - 9 - 8 - 7
3. Drag and drop some of the records at the top, this will trigger an AJAX save too, like you clicked a save button, thus your manual ordering will get saved too
4. DO a CTRL-F5 or similar refresh

Also if you want to add save button to the header of the column of e.g. featured manager
After:

<?php echo JHtml::_('searchtools.sort', '', 'fp.ordering', $listDirn ...

Add:

<?php echo JHTML::_('grid.order', $this->items, 'filesave.png', 'featured.saveorder' ); ?>

I have tested this item ✅ successfully on 40795cc

Tested

• articles manager
• featured mananager
• category manager

drag and drop works

also about manual editing ordering numbers, after you edit some of them and:

• either drag and drop some other row (to trigger save)
• or if you have a save button visible and you click

then the ordering is saved good in this case too

Also i forgot to mention

• removing the CSS that i used above to make the fields visible (thus default Joomla styling to have them hidden)

then re-ordering works in this case too for the 3 managers, and also tested menu manager

I have tested this item ✅ successfully on 40795cc

tested with admintools

2 good tests. Merging

I have tested this item ✅ successfully on 40795cc