[Resolved] Question about set_post_thumbnail and wpml_translate_single_string

Some additional context:

- for set_post_thumbnail:

I create a post programmatically and use wpml_set_element_language_details, I then create another post and link both using another call to wpml_set_element_language_details.

I then set media on the original post (which is always then present on all language versions) and set a post thumbnail on the original post too (which often is only set on the original post, but not on the translations).

- for wpml_translate_single_string:

I have an list of items with names in the original/default language. I loop through the items and register the strings.
I then, for each item, loop through all site languages and use wpml_translate_single_string. It always returns the original string and not the translation.

Bonus question: Could you briefly illustrate or explain the difference between wpml_translate_string and wpml_translate_single_string ? I don't seem to understand under which conditions one would prefer one to the other.

Thanks Andreas,

The media "duplication" (honestly, the configuration options are very confusing) works fine, it's just the thumbnail (or featured image) which is not automatically duplicated to (or rather referenced from) the translations.

There doesn't seem to be a hook equivalent to https://wpml.org/wpml-hook/wpml_apply_save_attachment_actions/ for thumbnails, thus I'm assuming I need to manually set the thumbnail on each post that I create, even if one is set as a translation of another one?

As for the translate_string vs. translate_single_string question, I think I see what the difference is. This is to avoid having whole Gutenberg or sitebuilder blocks or even pages show up in page translation.

Any idea though why my string translation could not be working or what I could check for to debug it?

I have noticed today, that thumbnails that I set manually on a post are actually being stripped from translations when they're programmatically being updated or linked.

The memory limit on this site is indeed a little low, all dependencies however are installed.
Let me look at the memory limit and then get back to you on this. Would appreciate if we could keep this ticket open in the meantime.

> "Duplicate media attachments for translations" should be activated, which will create duplicates of media while translating content, on which the original media file was uploaded directly.

So if I understand correctly, if, by the time I upload media, content (here, the parent post) is already translated, then the media would associate with both posts?

> If you do not duplicate media, then the original media files are not supposed to show up on any translation.

But they do 😉

See for example
- hidden link
- hidden link

At no point during the creation of these posts or the upload of the media was the "Duplicate media attachments for translations" checkbox checked.

Yes, I can see the same attachments in both languages, and no, I have not synced them manually.

I do want the images to show up in both languages… so that's good.

For now, I'm just seeking to understand the WPML configuration options and why it does what it does.

I talked to a few other WordPress devs, and none of them understood how these options actually work. They all just check some options and pray it does what they need.

I think we can close this ticket.