Users with author privileges cannot create a proper gallery

I encounter the same issue with the administrator user role on multisite. Only the superadmin can work properly with the gallery and slider blocks.

Trying to manage the role of the user I found the administrator role had the capability “Unfiltered HTML” unchecked, i.e. it was off. I activated it but that didn’t help. After I save a post/page that has a gallery I get the gallery in the front-end as static images preceded by some HTML code like the one below:
{„copyRProtection“:false,“copyRAlert“:“Hello, this photo is mine!“,“sliderScrollNavi“:false,“sliderNextPrevAnimation“:“animation“,“galleryScrollPositionControll“:false,“sliderItemCounterEnable“:false,“sliderCaptionSrc“:“caption“,“sliderItemTitleEnable“:false,“sliderItemTitleFontSize“:18,“sliderItemTitleTextColor“:“rgba(255,255,255,1)“,“itemCounterColor“:“rgba(255,255,255,1)“,“sliderThumbBarEnable“:false,“sliderThumbBarHoverColor“:“rgba(240,240,240,1)“,“sliderBgColor“:“rgba(0,0,0,0.8)“,“sliderPreloaderColor“:“rgba(240,240,240,1)“,“sliderHeaderFooterBgColor“:“rgba(0,0,0,0.4)“,“sliderNavigationColor“:“rgba(0,0,0,1)“,“sliderNavigationColorOver“:“rgba(255,255,255,1)“,“sliderNavigationIconColor“:“rgba(255,255,255,1)“,“sliderNavigationIconColorOver“:“rgba(0,0,0,1)“,“sliderSlideshow“:false,“sliderSlideshowDelay“:8,“slideshowIndicatorColor“:“rgba(255,255,255,1)“,“slideshowIndicatorColorBg“:“rgba(255,255,255,0.5)“,“sliderThumbSubMenuBackgroundColor“:“rgba(255,255,255,0)“,“sliderThumbSubMenuBackgroundColorOver“:“rgba(255,255,255,1)“,“sliderThumbSubMenuIconColor“:“rgba(255,255,255,1)“,“sliderThumbSubMenuIconHoverColor“:“rgba(0,0,0,1)“,“sliderSocialShareEnabled“:false,“sliderZoomEnable“:false,“sliderFullscreenEnabled“:false,“modaBgColor“:“rgba(0,0,0,0.8)“,“modalIconColor“:“rgba(255,255,255,1)“,“modalIconColorHover“:“rgba(255,255,255,0.8)“,“shareFacebook“:true,“shareTwitter“:true,“sharePinterest“:true,“sliderItemDownload“:true,“shareCopyLink“:true,“tagsFilter“:false,“tagCloudAll“:“All“,“tagCloudBgColor“:“rgba(153,153,153,1)“,“tagCloudBgColorOver“:“rgba(253,253,253,1)“,“tagCloudTextColor“:“rgba(253,253,253,1)“,“tagCloudTextColorOver“:“rgba(153,153,153,1)“,“tagCloudFontSize“:16,“deepLinking“:false,“useLightbox“:true,“numItemsDisplayed“:0,“lazyLoading“:true,“contentNoPadding“:false,“galleryPreloaderColor“:“rgba(230,230,230,1)“,“galleryBgColor“:“rgba(0,0,0,0)“,“galleryBorderRadius“:0,“collectionThumbRecomendedWidth“:200,“thumbSpacing“:5,“externalLink“:true,“externalLinkDefName“:“Read More“,“externalLinkTextColor“:“rgba(0,0,0,1)“,“externalLinkBgColor“:“rgba(255,255,255,1)“,“externalLinkFontSize“:18,“captions“:true,“captionSrc“:“caption“,“captionHAlign“:“top“,“collectionthumbHoverTitleFontSize“:18,“collectionthumbRoundedCorners“:0,“collectionthumbHoverTitleTextColor“:“rgba(255,255,255,1)“,“collectionthumbHoverTitleTextBgColor“:“rgba(0,0,0,0.8)“,“collectionthumbHoverBgColor“:“rgba(0,0,0,0.4)“,“collectionThumbSubMenuDownload“:false,“collectionThumbSubMenuShare“:false,“collectionThumbSubMenuBgColor“:“rgba(0,0,0,0.4)“,“collectionThumbSubMenuBgColorHover“:“rgba(255,255,255,1)“,“collectionThumbSubMenuIconColor“:“rgba(255,255,255,1)“,“collectionThumbSubMenuIconColorHover“:“rgba(0,0,0,1)“,“galleryType“:“pgc_sgb_slider“,“galleryId“:“0b4eed0d_1611957629638″,“images“:[{„id“:2049,“title“:“ris“,“url“:… etc.

When I go back to edit the post/page I find the gallery block showing this warning:
The block contains unexpected or invalid content. Try to restore the block.

When restoring it like super admin it saves properly but no other role can do it.

Sure, I understand that, so I gave that user the right you mention. Nevertheless, though he can restore the broken block right after hitting Save the block gets pale and brakes again.
You can access a test site with the problem here: https://megatron.bg/msite/test/wp-admin/
Superadmin credentials: xseon with pass 12-QWE-34
The other user: despet with pass des5rov
Go edit page ‘Начало’ when logged in as despet: https://megatron.bg/msite/test/wp-admin/post.php?post=2066&action=edit and just save the page. Then you’ll see the block brakes (fron-end: https://megatron.bg/msite/test/).
You can check the users capability and see the Unfiltered HTML box is checked for the groups despet is in.
Am I missing something?

Thank you, Unfiltered MU solved the problem right away. Maybe you could incorporate it into your plugin to save its users all the trouble.