But I noticed a problem when embedding a video from YouTube. The propostions do not addapt to smaller screens. It shows very big black bars on top and bottom
Please see screenshots.
How can we fix this? (preferably without a plugin).
@rampatter You have shared page URL which describes how to embed youtube video in HTML page.
First of all this forum is for WordPress themes and not for HTML pages and the topic creator has asked question to remove big black bars from youtube video and not about embedding video therefore your reply here is wrong and invalid.