UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36

Steps to reproduce the problem:
1. Write a custom formatter, particularly one for a compile-to-Javascript language
2. Wish that you could have a link to the sources when hovering over a definition, like you get when hovering over JavaScript functions etc. that don't have a custom formatters.

What is the expected behavior?

What went wrong?
The native previews go through https://cs.chromium.org/chromium/src/third_party/WebKit/Source/devtools/front_end/object_ui/ObjectPopoverHelper.js?rcl=cc61189ef4d8fbe9cd8d7783168a075b6b1a8bcc&l=138

and have a linkifier, so if you hover over e.g. a function you get a nice link to the sources. But if there's a customPreview the set of available tags is constrained by a whitelist, so you can't add a link yourself. The source link that would be in the regular preview is also not shown in favour of the custom preview.

Did this work before? No 

Chrome version: 65.0.3325.181  Channel: stable
OS Version: Debian
Flash Version: 

Being able to have links in general would be nice, but I can imagine there would be security implications. Being able to have an indicator that the source link as in the non-custom preview was desired would be a bit of a one-off, but presumably has no security implications.