When reloading the form of an issue on which for example we have changed
the value of a select, the browser remember the previous value selected
and ignore the selected option.
To prevent this, the select must have autocomplete set to 'off'
https://developer.mozilla.org/en-US/docs/Web/HTML/Element/input#attr-autocomplete
I do not know if it is better to just add it to the form attribute in
each templates or if the templating menu() should set it.

I am confused. As far as I can tell the autocomplete attribute
only works for input (mostly text) tags.

As you state, menu() creates a select. From what I see at the w3c
autocomplete is not valid for selects. The link you posted
references input elements. If autocomplete does anything for
selects, I think it's a bug.

I can reproduce your issue. However in firefox shift refresh does
return the original (reset) data for selects at least. This makes
me wonder if firefox is trying to prevent data loss (or is pulling
from a local cached copy with the change preserved) and causing
the issue you report.

Refreshing/reloading with Edge, IE, Opera and Chrome are all
resetting the select box to the unchanged value. So this looks like
some ff issue.

Having said that, other types of input (e.g. checkbox) may benefit from
setting autocomplete off.  However from what I see of autocomplete use,
I would not expect the autocomplete type: name, street-address, ... to
be set on a checkbox.

As a result I am not sure that autocomplete will even do anything
useful for a checkbox.

Setting autocomplete="off" on the form tag may not be a bad idea.
It probably depends on the specific use case of the tracker.
As a result specifying it in the html for the specific tracker
instance rather than putting it into the code that generates form
fields is probably a better idea.

So my suggestion at this time sine it only appears firefox
is a problem is that there is nothing to change
in the released code for this. However an addition to the
documentation may be useful.

-- rouilj

Additional links:

  https://bugzilla.mozilla.org/show_bug.cgi?id=46845#c13
from
  http://forums.mozillazine.org/viewtopic.php?f=25&t=226839

Apparently keeping values on reload (not shift reload) is
intentional to prevent loss of work on reload.