There's an event triggered when entering In-place edit mode, `xwiki:actions:edit`, that we can listen to and remove that warning. Check what the lightbox does for instance https://github.com/xwiki/xwiki-platform/blob/master/xwiki-platform-core/xwiki-platform-image/xwiki-platform-image-lightbox/xwiki-platform-image-lightbox-webjar/src/main/webjar/lightbox.js#L465 .
