For some time Calibre2opds has had a browser based search feature that has been labelled as experimental. It has been decided to change the status of this feature to ‘deprecated’ (although we have not yet removed it from the Calibre2opds program).
The reason for this is that the Calibre2opds search feature was based on the draft HTML 5 database feature (commonly known as WebSQL) that was going through the standardisation process. However this specification has since been withdrawn and is deprecated by the W3C standardisation process. A consequence is that major browser such as Internet Explorer and Firefox have decided not to support this feature. Browsers that DO appear to support it are Safari, Chrome and Opera but since this feature is no longer up to be standardised support could well be removed in future versions.
If you decide that you DO want to generate a Calibre2opds catalog to support this feature, then if you use a browser that is not compatible with the current implementation then you will now get an error message stating this when you try and use search.
If anyone can point out any open-source libraries that implement browser side databases in a manner compatible with all major browsers then we would be happy to look at changing the Calibre2opds search feature to utilise such a library.