On odd occasions, if you have OPACFRBRizeEditions or FRBRizeEditions set to "Show" and you are using a FRBR service like ThingISBN, the full record display will load so loading that it times out with a Plack proxy error. I believe this is related to the length of the API return from ThingISBN. An example would be ISBN 9781913755201. https://www.librarything.com/api/thingISBN/9781913755201 This API call returns many hundreds of ISBNs and the Editions tab in Koha is not able to load and process the response. Not sure how we address this, whether we add a limit to the results returned, add some pagination or "click here for more"?