Secondary Level of Tabs Missing

These tabs do appear for me in Gin. But this seems odd. I can't think of any normal setting that would turn these off.

Maybe another contrib module you have? Also, try rebuilidng cache after changing themes?

Thank you for replying @paul121! It got me digging and I remembered that blocks are theme-specific. And sure enough that block was missing in my theme. I added it back (Tabs block, and uncheck Primary in the Shown Tabs section, leave Secondary checked). A very simple solution to something that has been bothering me for a while!