Bugzilla

The Choice widget allow only the selection of one element (`Ff = 131023 === 2^17`) and has an entry `I` with a value of  `[0]` which should be used only when multiselect is enabled, from the pdf specs (about `I` entry):
```
For choice fields that allow
multiple selection (MultiSelect flag set), an array of integers, sorted in ascending
order, representing the zero-based indices in the Opt array of the currently
selected option items. This entry shall be used when two or more elements in the
Opt array have different names but the same export value or when the value of
the choice field is an array. This entry should not be used for choice fields that do
not allow multiple selection. If the items identified by this entry differ from those in
the V entry of the field dictionary (see discussion following this Table), the V entry
shall be used.
```
And as far as I can tell Acrobat is using the `I` value when it shouldn't, because when I remove the entry from the annotation dictionary the rendering is correct in Acrobat.
So from my point of view, there are 2 issues here:
 - the pdf generator wrongly added a `I` entry;
 - Acrobat and Okular (Windows version) are using this entry to choose the selected value.

On the Firefox' side, we can "fix" a saved pdf when it has been modified by the user in removing the `I` entry, but unfortunately we cannot do better.

The Choice widget allow only the selection of one element (`Ff = 131072 === 2^17`) and has an entry `I` with a value of  `[0]` which should be used only when multiselect is enabled, from the pdf specs (about `I` entry):
```
For choice fields that allow
multiple selection (MultiSelect flag set), an array of integers, sorted in ascending
order, representing the zero-based indices in the Opt array of the currently
selected option items. This entry shall be used when two or more elements in the
Opt array have different names but the same export value or when the value of
the choice field is an array. This entry should not be used for choice fields that do
not allow multiple selection. If the items identified by this entry differ from those in
the V entry of the field dictionary (see discussion following this Table), the V entry
shall be used.
```
And as far as I can tell Acrobat is using the `I` value when it shouldn't, because when I remove the entry from the annotation dictionary the rendering is correct in Acrobat.
So from my point of view, there are 2 issues here:
 - the pdf generator wrongly added a `I` entry;
 - Acrobat and Okular (Windows version) are using this entry to choose the selected value.

On the Firefox' side, we can "fix" a saved pdf when it has been modified by the user in removing the `I` entry, but unfortunately we cannot do better.