Fix unable to select items in a multi-picklist #953

[MortimerGoro]

No description provided.

[cvan]

Test case to use (the third field down):

• https://webxr.sh/forms, select #25
• https://mdn.github.io/learning-area/html/forms/native-form-widgets/drop-down-content.html

[cvan]

👍 Nice work, @MortimerGoro. This fixes the original issue. There are a few items I wanted to still address.

I noticed a few inconsistencies and bugs, primarily an issue with the <option>s not being properly highlighted upon being checked (selected) in a <select multiple> field. If this is a GeckoView issue, let's file there.

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In FxR, in a rendered <select multiple> on the page, when any values (e.g., the first two values) are selected, the rows are not properly highlighted as they are in Firefox for desktop:

Notice that in FxR only the first row is ever "highlighted" (with the faint-blue focus ring):

Compare with Oculus Browser:

1. Load <select multiple> test on https://webxr.sh/dropdowns#multiple.

2. Notice the default text will read Cherry (but if you modify the value and then reload the page, it will continue to read 2 Selected).

   
   

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1. In Oculus Browser, Firefox Reality, and Firefox for desktop, scroll to https://webxr.sh/dropdowns#multiple.
2. Press the <select multiple> field, and press the rows such that four items are selected.
3. Press the checkmark icon to submit the changes.
4. Notice the text changes from -- Please choose one or more -- to 4 Selected.

In Oculus Browser:

in FxR:

vs. in Firefox for desktop:

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also, I filed #1007 for an issue I noticed with <option disabled> (example):

[MortimerGoro]

@cvan can you reproduce the highlight issue consistently? I tried many times and only was able to reproduce it once. At the same time #1007 happened too, but not on the others attemps. So I think they are related and it's a GV bug, because the values in the prompt are kept selected correctly.

[bluemarvin]

@cvan trying to roll a release. Any additional issues can be handled in follow up.

[cvan]

@cvan can you reproduce the highlight issue consistently? I tried many times and only was able to reproduce it once. At the same time #1007 happened too, but not on the others attemps. So I think they are related and it's a GV bug, because the values in the prompt are kept selected correctly.

I can consistently reproduce on Oculus Go and Pico G2 (WaveVR) the highlight issue with <option selected> in <select multiple> issue. I've filed issue #1013.

I can also consistently reproduce (#1007 (comment)) the bug with the hidden text in <option disabled>. thanks for filing GeckoView bug 1535275 to track.