therealreiti

Thanks for your reply!
Unfortunately, I am not a 100% sure what you mean.
The errors in the console (or if i click “copy error”) are:

TypeError: Failed to execute 'appendChild' on 'Node': parameter 1 is not of type 'Node'.
    at de (https://coco-study.org/wp-content/plugins/gutenberg/build/rich-text/index.min.js?ver=8c8864de15088443cbca75e2aba2710e:1:19671)
    at le (https://coco-study.org/wp-content/plugins/gutenberg/build/rich-text/index.min.js?ver=8c8864de15088443cbca75e2aba2710e:1:18610)
    at be (https://coco-study.org/wp-content/plugins/gutenberg/build/rich-text/index.min.js?ver=8c8864de15088443cbca75e2aba2710e:1:20112)
    at Te (https://coco-study.org/wp-content/plugins/gutenberg/build/rich-text/index.min.js?ver=8c8864de15088443cbca75e2aba2710e:1:20550)
    at T (https://coco-study.org/wp-content/plugins/gutenberg/build/rich-text/index.min.js?ver=8c8864de15088443cbca75e2aba2710e:5:8967)
    at N (https://coco-study.org/wp-content/plugins/gutenberg/build/rich-text/index.min.js?ver=8c8864de15088443cbca75e2aba2710e:5:10199)
    at https://coco-study.org/wp-content/plugins/gutenberg/build/rich-text/index.min.js?ver=8c8864de15088443cbca75e2aba2710e:5:11429
    at https://coco-study.org/wp-content/plugins/gutenberg/build/compose/index.min.js?ver=cdf5122fe9aebc0dda95dc229614060e:1:22435
    at P (https://coco-study.org/wp-content/plugins/gutenberg/build/compose/index.min.js?ver=cdf5122fe9aebc0dda95dc229614060e:1:25617)
    at https://coco-study.org/wp-content/plugins/gutenberg/build/compose/index.min.js?ver=cdf5122fe9aebc0dda95dc229614060e:1:26052

In addition, inspecting the error box gives:
<div id="editor" class="block-editor__container hide-if-no-js"><div><div class="editor-error-boundary block-editor-warning"><div class="block-editor-warning__contents"><p class="block-editor-warning__message">The editor has encountered an unexpected error.</p><div class="block-editor-warning__actions"><span class="block-editor-warning__action"><button type="button" class="components-button is-secondary">Attempt Recovery</button></span><span class="block-editor-warning__action"><button type="button" class="components-button is-secondary">Copy Post Text</button></span><span class="block-editor-warning__action"><button type="button" class="components-button is-secondary">Copy Error</button></span></div></div></div></div></div>

• This reply was modified 2 years, 9 months ago by therealreiti.

Thanks for your feedback!
I totally understand the flaws and problems of using an image as H1 and know that this is a stupid idea in terms of SEO!
However, SEO is not the biggest target for this website as we mainly focus on using the website for informing participants of our project about the project. For this we wanted to create a somewhat representative website to serve this objective.
If we would have an easy solution to create the same kind of heading with a proper H1 (that results in same looks without having a major restructuring of the website) I would be totally fine.
So far our (not very elegant) solution worked. This was why my initial question was whether there is any solution to get back to our status quo of one week in the face of the WP update… But it seems as if there would not be any…

Thanks for your reply!
I am using twenty-twenty theme and just put the html code snippet for inserting an image from my media library into the field that carries the H1 (i.e., I just put the <img src=”” container into the H1 field).

Until version 5.8.3 (I think that was the previous version before 5.9) the block editor was able to handle this and and perfectly showed me the respective pictures from the html image code in the editor (edit and preview mode) and on the final website.
However, after having the 5.9 update this does not work anymore.
Is there any way of getting it back to work? E.g., by embedding the images via PHP

Changing back to classic editor worked by downloading the “classic editor” plugin and the via settings -> writing -> Editor style

I also think I figured out what my problem was/is.
I am using images in some H1s of my pages (so the actual h1 is something like which WordPress 5.9’s block editor does not seem to allow (due to… reasons).
I think I’ll hope for an update/patch and stick to the block editor so far as I do not want to change the entire site appearance due to this issue.
Is this the same in your case? i.e., are you also having images as H1

best

Unfortunately no solution, but I am having the same problem for some days now (maybe due to the WP Update to 5.9 some days ago):

Things I found as possible solutions but that didn’t seem to solve the problem so far were:

-updating browser
-cleaning browser cache
-cleaning wp cache
-disactivating all installed plugins
-using troubleshooting mode of site health plugin

When Installing and selecting classic editor I can access my pages in classic editor. However when changing back to block editor the error re-appears.

Any additional ideas?

As I think this might be relevant: I am using twenty-twenty theme