Thierry

Issue opened for the Gutenberg plugin: https://github.com/WordPress/gutenberg/issues/5920

It definitively is. When I revert to the classic editor, the screen options are available, but in the Gutenberg editor they aren’t, so that I even did not think about that possible cause of the issue. That must have led to my confusion. Silly me! Thank you again for your precious help!

• This reply was modified 6 years, 7 months ago by Thierry.

Found it. Can’t understand why this happened, but in the user_meta table there was an entry key metaboxhidden_post, where the plugin was listed in the value field. After setting back the value to a:0:{}, the box is visible again. Please accept my apologies for your waisted time!

Javascript is on, in Safari/Mac, in Firefox/mac and in Safari/iOS.

I do not longer think that it is a unique headers plugin problem since I see it on different platforms. Seems rather to be a problem with my WP install. Will try to setup a new one on a different server in the next days and see what happens.

In ever case, thank you for your time and investigating.

BTW: Even when deactivating all other plugins but Gutenberg, the problem is the same. It does not depend on the Theme either, happens with twenty twelve and with twenty seventeen.

Getting closer… Just checked the editor page’s source code. The meta box is there, but it’s hidden (on my macbook in Safari and Firefox as well as on the iPad) because of the hide-if-js class:

<div id="custom-header-image" class="postbox  hide-if-js" style="">
<button type="button" class="handlediv" aria-expanded="true"><span class="screen-reader-text">Toggle panel: Custom header</span><span class="toggle-indicator" aria-hidden="true"></span></button><h2 class="hndle ui-sortable-handle"><span>Custom header</span></h2>
<div class="inside">
<input type="hidden" id="custom-header-image-nonce" name="custom-header-image-nonce" value="09fd2bc93a"><input type="hidden" name="_wp_http_referer" value="/wp-admin/post-new.php">
		<p class="hide-if-no-js" style="display: none;">
			<a title="Set Custom Header Image" href="javascript:;" id="set-custom-header-image-thumbnail" class="set-custom-meta-image-thumbnail">Set Custom Header Image</a>
		</p>

		<div id="custom-header-image-container" class="custom-meta-image-container">
			<img src="https://theremin.academy/wp-content/uploads/2018/03/berlin2018-e1521403756853.jpg" alt="" title="berlin2018">
		</div><!-- # -->

		<p class="hide-if-no-js hidden">
			<a title="Remove Custom Header Image" href="javascript:;" id="remove-custom-header-image-thumbnail" class="remove-custom-meta-image-thumbnail">Remove Custom Header Image</a>
		</p><!-- .hide-if-no-js -->

		<p id="custom-header-image-info" class="custom-meta-image-info">
			<input type="hidden" id="custom-header-image-id" class="custom-meta-image-id" name="custom-header-image-id" value="1570">
		</p><!-- #custom-header-image-image-info --></div>
</div>

Why could that class be added? When I deactivate temporarily the associated display: none; the meta box is shown and operational.

• This reply was modified 6 years, 7 months ago by Thierry.

So, it might either be another plugin which causes trouble (will have to deactivate theme one by one) or it is a Safari problem (will install chrome) and report back.

Unfortunately, I can’t see a way to attach screenshots here, but I look the right sidebar in the page editor up and down, unfold all possible options, but there is no option for the unique header displayed.

• This reply was modified 6 years, 7 months ago by Thierry.

Thank you in advance!

It does still not work for me since I don’t understand the discussion above. I’m using a child theme based on twenty fifteen and there is no category.php file. Thus, please tell me which file from the twenty fifteen theme I have to modify and how after having it copied over to the child theme.

Actually, the page is still showing the old category header although I used enhanced edit to add a custom header image to that category:
https://theremin.tf/category/projets/

Thank you in advance