role="auto" unnecessarily added to images.

[DennisSuitters]

Checklist

• I've looked at the documentation to make sure the behavior isn't documented and expected.
• I'm sure this is an issue with Leaflet, not with my app or other dependencies (Angular, Cordova, React, etc.).
• I've searched through the current issues to make sure this hasn't been reported yet.
• I agree to follow the Code of Conduct that this project adheres to.

Steps to reproduce

When running page speed insights, the following is reported as an accessibility error on the role attribute being set to auto:

<img src="[URL]" class="leaflet-marker-icon leaflet-zoom-animated leaflet-interactive" alt="Marker" tabindex="0" role="auto" style="margin-left: -12px; margin-top: -41px; width: 25px; height: 41px;">

The role attribute is not required in this instance, as the image is not masquerading as another element, making role redundant.

Expected behavior

That the generated markup via the script isn't unnecessarily adding attributes.

Current behavior

The role attribute does not need to be added to images, as role="image" or role="auto". The only time a role attribute is required is to tell the browser that the current element is a particular function, or if the current element is masquerading as another element, for e.g. a link being a button.

Minimal example reproducing the issue

No response

Environment

• Leaflet version: 1.9
• Browser (with version): Chrome (latest), but irrelevant in this case.
• OS/Platform (with version): Linux

[Falke-Design]

@Malvoz some thoughts from you?

[Malvoz]

For markers we're only setting:

Leaflet/src/layer/marker/Marker.js

Line 238 in 80a4276

icon.setAttribute('role', 'button');

See all instances of "role": https://github.com/search?q=repo%3ALeaflet%2FLeaflet%20role&type=code

@diemendesign auto is an invalid role value. Which URL did you analyze? Do you have a screenshot of the PageSpeed Insights results? Was a plugin in use?