As mentioned in commits 5311daadf and bb958daf0, using links combined
with JavaScript to generate POST (or, in this case, DELETE) requests to
the server has a few issues.
This is the reason why this feature was implemented in the first
place: it's easy to open the editor, make some changes, close it, and
continue without realizing the changes have not been saved.
In the rest of the forms, this functionality is quite lacking. For
starters, some forms warn if there are unsaved changes, while some forms
don't, which is highly inconsistent and disorients users.
Furthermore, we were having problems with this feature after upgrading
Turbolinks, particularly in forms using CKEditor. In these cases, a lot
of hacking needs to be done in order to make this feature work properly,
since CKEditor adds some formatting automatically, and if this is done
after the form is serialized, we'll get some unexpected behavior. On the
other hand, comparing the value of a textarea against its `defaultValue`
property will work on every edge case, including using the browser's
back button or reloading the page.
Finally, users are used to the way web forms work, and aren't used to be
asked for confirmation when they change their mind and decide to leave
the page without saving the changes. Asking them for confirmation will
be annoying in most cases. Besides that, if they accidentally leave the
page, they can use the browser's back button and they'll recover the
unsaved changes.
It's true this won't happen it they accidentally close the browser's
window, but our WatchFormChanges functionality didn't work in this case
either. Using the "beforeunload" event adds more problems than it
solves, since it doesn't support custom messages (or, to be more
precise, modern browsers ignore custom messages), and it doesn't get
along with turbolinks.
Co-Authored-By: Senén Rodero Rodríguez <senenrodero@gmail.com>
