[davidfor]

Originally Posted by 2nise

I see. Since Kobo is helping create the Tolinos since a few years ago, and the readers do look quite similar (both in hardware and software), so I just assumed they'd function similarly, too. Thanks for the correction.

Kobo own a chunk of tolino and are sharing hardware. But, the firmware is completely different.

I've tired different version of this:
{series:ifempty('tags')}

I've tried using field(tags) in the ifempty bracket, as well as different versions using the apostrophe/not using them. I also tried using a predefined text/folder and custom field instead of the tags field, but no difference.
I assume it's just a dumb syntax error from me misunderstanding the template language, but I honestly am out of ideas now

You can try:

{:'ifempty(field("series"),field("tags"))'}

But, I don't think it will do what you really want. That will create a collection for each combination of tags you have in the books.

The following will use just the first tag for each book:

{:'ifempty(field("series"),list_item(field("tags"),1,","))'}

And the following won't sort the tag list first:

{:'ifempty(field("series"),list_item(raw_field("tags"),1,","))'}

If you wanted to use single collection for all non-series book, you can use:

{series:ifempty(non-series)}

Hopefully one of those will work, or give you an idea of what to do.