Slider content lost after updating slider

I had to change some text in an existing slider and when I opened the slider (which has been running correctly for months), I noticed that the <video><source></video> tag was missing.
I then corrected the part and it looked like this:

<video id="video1" preload="true" autoplay="false" muted="" playsinline="true" loop="true">
<source src="https://www.elastomer.kuraray.com/wp-content/uploads/2021/10/kuraray_slider_medical.mp4" type="video/mp4"/>
</video>

After updating the slider, the <source> code is missing.
Instead, the code in the slider editor (Disable Visual Editor is checked) shows a blank line:

<video id="video1" preload="true" autoplay="false" muted="" playsinline="true" loop="true">

</video>

Tried downgrading the SA slider plugin to an older version but this did not solve the issue.
This is a Multi Site and on the other instances (didn’t dare to edit the slider in the other languages after I noticed the error), the videos are loaded correctly: https://www.elastomer.kuraray.com

The system info shows that the php_value max_input_vars is set to 10000

Any ideas?
As I said, all the sliders were running correctly for months.

• This topic was modified 1 year, 10 months ago by tonfarbe.

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