One problem with hexdigest is that it's longer and the column was
created as binary(16). We don't have a mechanism to run migrations on
this table, so we use UNHEX in SQL to have the equivalent as digest()
from hexdigest()
Co-authored-by: Jérome Perrin <jerome@nexedi.com>

also str representation of unicode character is different.

This only works on python2

for same reason as the xhtml_style version, there is no problem with
having more than one listbox, see d2dedca3 (core: remove useless log
in Base_callDialogMethod, 2020-07-03)

Use same label as the action, "Preview"

These scripts take time to run, so restrict them to Manager users.