I have tested this item ✅ successfully on d118e72

This is what I get

Display looks weird to me.

@infograf768 Are you referring to the fact that the switchers are only grey when deactivated? I fixed this in #26360. Or is there something else?

@Harmageddon
Not only that but the fact that the labels Show Original file and Show Differences are redundant with the switcher state and are far away from the switcher. Also when window is narrowed, they go over the Editing File...etc.
The labels should be: Original File and Differences (and next to the Switcher) and the switcher could just use Show and Hide imho.

We have a similar issue in the Template Style Edit with label and switcher state where we should have as label Layout (once only and not twice...) instead of Fluid Layout, but in this case, happily, the label is over the switcher.

There is already a PR for the double text

Tbh, I'm not sure whether these changes belong here or in #26360, but I just included them here. Should look better now. Now, it is required to test the switchers in other places, too, to make sure I didn't mess them up. From global configuration and some modules, it looks fine to me.
Though I'm not sure about the RTL stuff, but as far as I see, there is no RTL language able to be installed, so I can't really check that.

@Harmageddon Persian is RTL and should work.

Thanks @richard67! To me, it looks good now. But @infograf768, maybe you might want to check, as you are an expert of RTL compatibility IIRC? ;-)

will do tomorrow

Works quite fine. Thanks.
Just needs a small change in the switcher.scss

For a reason that I ignore, we have in LTR a padding-right: 5px; for .switcher__legend

if we don't want to keep this padding, we just have to delete it from the LTR part.
If we want to keep this, then we have to modify for RTL from:

.switcher__legend {
  margin-bottom: 1rem;
  font-size: 1rem;
  font-weight: 400;
  float: left;
  width: 220px;
  padding-top: 5px;
  padding-right: 5px;
  text-align: left;

  [dir=rtl] & {
    float: right; 
    text-align: right;
  }
}

to

.switcher__legend {
  margin-bottom: 1rem;
  font-size: 1rem;
  font-weight: 400;
  float: left;
  width: 220px;
  padding-top: 5px;
  padding-right: 5px;
  text-align: left;

  [dir=rtl] & {
    float: right;
    padding-left: 5px;
    padding-right: 0px; 
    text-align: right;
  }
}

NOTE

Just to remember. Unrelated to this patch.
In RTL we need to force use text-align: left; for the editor textarea.
We also need to correct the tree in administrator/index.php?option=com_templates&view=template&id=202&file=aG9tZQ==

See Tree correction in #26367

You're absolutely right, thank you for the good spot @infograf768!

I have tested this item ✅ successfully on 09be866

@richard67 please test again

@infograf768 Am already preparing my environment for this ?

I have tested this item ✅ successfully on 09be866

@infograf768 RTC ;-)

RTC

Thanks!