I found the problem: it was the Enhanced Media Library plugin. The is an option that should be activated because this plugin is currently in conflict with Jetpack Tiled Galleries. This option is:
Turn off enhanced gallery
Do not enhance WordPress native gallery shortcode
The help text says:
May be useful in case of incompatibility with other plugins or themes. Use the option if you think it breaks your galleries in any way.
Please inform plugin authors about the issue. We would like to fix it!
I did inform the authors ??
Let’s see how it evolves.
