Parameter providing search-by-image feature for the default search provider

If DefaultSearchProviderEnabled is on, then setting DefaultSearchProviderImageURL specifies the URL of the search engine used for image search. (If DefaultSearchProviderImageURLPostParams is set, then image search requests use the POST method instead.)

Leaving DefaultSearchProviderImageURL unset means no image search is used.

If image search uses the GET method, then the URL must specify image
parameters using a valid combination of the following placeholders:
'{google:imageURL}',
'{google:imageOriginalHeight}',
'{google:imageOriginalWidth}',
'{google:processedImageDimensions}',
'{google:imageSearchSource}',
'{google:imageThumbnail}',
'{google:imageThumbnailBase64}'.

Example value: https://search.my.company/searchbyimage/upload