Gallery not showing in columns

Hello,

we’re happily using the BAM-Theme for a pupil’s magazine of an elementary school.

But for quite a while now we’re having some issues with the display of images in posts. The most important one regards the WP-gallery-block: When it is set to e. g. three columns, this works in the WP-editor (backend). However, on the website the images are displayed in one column (one image below the other), more than three columns or a mixed version of both.

I’m aware that current WP-versions seem to have an issue with missing specifications for the CSS-class .is-layout-flex applied to the gallery-tag <figure>. The recommended solution is to add the following CSS-code in the Customizer:

.is-layout-flex {
	display: flex;
	flex-wrap: wrap;
}

However, in our case this doesn’t help. :-/

Yet somewhere else I read that in some themes theres a conflict with the original WP-attribute

display: flex

being replaced by

display: block

Could this be the case with the BAM-Theme – and is there a solution available to get the gallery-block working?

Thank you for any help!
Oliver

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