Embedded Youtube Fullscreen Button Missing in Chrome

When playing an embedded youtube video, inserted into a Confluence page using the Widget Connector, using Chrome it does not have the fullscreen button. I have tested this in the reported 5.4.3 and verified it still behaves this way in 5.5.4

Reproduction steps:

1. Embed a Youtube video into a Confluence page using the Widget Connector
2. In Chrome, navigate to the page and play the video
3. There will be no fullscreen button in the bottom right corner

Expected behavior

There should be a fullscreen button in the bottom right corner.

Actual behavior

There is no fullscreen button in the bottom right corner of the video.

Related Notes

• The fullscreen button does appear using Safari and Firefox.

Workaround

The workaround is to not use the Widget Connector, but embed the YouTube video directly in the page using the (disabled by default) HTML Macro

1. Enable the HTML Macro
2. Go to a page you want to have a YouTube video embedded
3. Add an empty HTML Macro to the page
4. Go to the YouTube video you want to embed
5. Click the Share button in the video
6. Click the Embed Tab
7. Copy the full HTML code provided
8. Paste that into the HTML Macro in the Confluence page
9. Save the Page