Additional attributes get stripped

ravi kant → made their first commit to this issue’s fork.

I am getting same issue.
"frameborder" is deselected when editing iframe after set true to "frameborder"

The issue may be due to deprecated options so i have created a separated ticket for all deprecated options 🐛 Deprecated option "align (deprecated)" is creating issue. Active .

(fixing iframe code)

For each attribute in an iframe, we need to add explicit support for it. This issue needs to be reframed to list out specific attributes we need to support. I don't think "allowtransparency" is a real attribute (it's not listed here).

The "loading" attribute is a real one, and we should add support for that.

I would really like to see Class added as an option here:

According to Mozilla, global attributes like class are allowed in iframe tags.