Collapsable Text Box behaving differently than before, wish to restore original behaviour

Question:
[ I wish to recreate the behaviour of a collapsable text box element as I had it designed until a few weeks ago, when behaviour changed without altering settings. Possibly through inserting some custom code, although I have no experience with this in WIX yet. Thank you ]

Product:
[Wix Editor]

What are you trying to achieve:
[I’ve just designed my first Wix website over the past 2 months. Next to media shown on pages, I’ve designed ‘credits’ elements out of a collapsable text box, showing additional info about the images/videos. I’d determined the settings so that no text is visible (not even the 1st line) when the box is collapsed, and text appears only when clicked. It worked fine until 2 weeks ago the behaviour of the collapsable text box changed without altering settings, and now the first line of text is always visible, interfering with the overall design of the pages. So far, customer service has not been able to help me restore the functionality of the original design. I’ve tried other elements to simulate a similar kind of behaviour, but am not happy with the results. I am looking for advise/help to achieve again the original behaviour of the element, possible through inserting some custom code]

What have you already tried:
[tweaking other elements suggested by customer care]

Additional information:
[for example, https://www.martijntellinga.nl/presence-un-presence shows the issue, top right above the picture gallery used on that page. I wish to make the first line of text disappear when the text box is collapsed]

Do you have page code that isn’t working? Can you share it if so?

only worked with settings of standard elements, no coding yet. I guess I would need some custom code to make the collapsable text box behave again as it did until some weeks ago…