Failed to store record in an IDBObjectStore: BlobURLs are not yet supported.

I am getting this error Failed to store record in an IDBObjectStore: BlobURLs are not yet supported. in ios 11 safari. To my knowlege (caniuse), this is incorrect, and bloburls are supported in this browser.

In the following code, icimageStore.put is where the error is thrown from.

    function populateIcImageTable(xml, clearIdbData, imageUrl) {

        const dbPromise = idb.open(idbHelper.databaseName, idbHelper.databaseVersionNumber, idbHelper.setupDatabase);

        let imageBlob;
        // fetch blob
        imageBlob = xml.response;

        // workout image key from the image filename
        const icimageKey = getImageKeyFromUrl(imageUrl);

        if (icimageKey === null){
            // Silently exit as we don't care if the icimage URL is invalid and its highly unlikely that it would be.
            return true;
        }

        // populate pdr table
        dbPromise.then(function (db) {
            const tx = db.transaction('icimage', 'readwrite');
            const icimageStore = tx.objectStore('icimage');

            // clear the existing data?
            if (clearIdbData){
                icimageStore.clear();
                console.log('icimage: store clear requested');
            }

            return icimageStore;

        }).then(function(icimageStore){

            // empty the table before updating it.
            if (clearIdbData) {
                console.log('icimage: store cleared');
            }

            return icimageStore.put({
                icimageKey: icimageKey,
                imageUrl: imageUrl,
                imageBlob: imageBlob

            });

        }).then(function () {

            console.log('icimage stored');

        }).catch(function(e){

            if (Raven){
                Raven.captureException(e);
            }

            console.error(e.stack);

            console.log('Error storing icimage for : '+e);
            displayNotification('danger', 'There was a problem updating the interchange image cache, please try again.', e, 'timeout');

        });

    }

Below is the log. 61089.JPG is the last image and apparently it is stored correctly.

This bug may be due to my code, but it seems like an incorrect error message at least. Thanks.

[jakearchibald]

Filed https://bugs.webkit.org/show_bug.cgi?id=188438

[jakearchibald]

There’s nothing I can really do about this, but I’ve reached out to Safari folks https://twitter.com/jaffathecake/status/1027546666721796097.