Solution:

diff --git a/templates/cassiopeia/scss/blocks/_form.scss b/templates/cassiopeia/scss/blocks/_form.scss
index 3889dbb..cb07f51 100644
--- a/templates/cassiopeia/scss/blocks/_form.scss
+++ b/templates/cassiopeia/scss/blocks/_form.scss
@@ -85,8 +85,10 @@
 
   &[id^=editarticle-] {
+    right: auto;
     margin-inline-start: -10em;
   }
 
   &[id^=editcontact-] {
+    right: auto;
     margin-inline-start: -10em;
   }

RTL!

What about RTL? Have you tested ????

If you set right to auto then there is no need for the margin-inline-start

indeed, we don't need it either in ltr...

Therefore it is not RTL specific.

and in RTL it would be (Without margin-inline-start: -10em;)

So, do whatever you want. I don't care at all.

EDIT NOTE:
taking off margin-inline-start will hide the tip when there is no right (or left in RTL) column position and reducing window.

Making patch now.

See #33066