What is avif & webp Replacement Feature?
"webp Replacement" is a feature included in the LiteSpeed Cache plugin for WordPress. This function occasionally replaces the images displayed in Wordpress with images in webp format, provided a browser supports this image format. In order to be able to use this function, you need a quic.cloud account, since webp images are not created on your own server, but externally by a quic.cloud service. Depending on whether you have the free or paid plan, the limit on the free plan is limited to 200 images per day. If you do not want to invest any money in the paid plan, the conversion of all images can sometimes take several weeks, since there is also a monthly limit there.
Images in webp format are characterized by the fact that the file size is significantly smaller than conventional images in .png or .jpg format, but not generally. It can happen that a jpg image has a smaller file size, although this is rarely the case. Although the webp format has been around for several years, not all browsers support this image format. As a rule, mostly Apple devices and other older browsers from other manufacturers are affected. It therefore needs a function that detects certain browser features and uses the supported image format depending on them. Independent of the LiteSpeed Cache plugin, this detection is very error-prone, especially with Apple devices, since Apple only provided the features required for clear detection in Safari browser version > 16.3. With older Safari browser versions, this can lead to incorrect behavior when displaying the image. The LiteSpeed Cache plugin has a high detection rate, but only on the iPhone. iPad and desktop devices are not supported at all.
As advantageous as the webp format may seem, there is a much more powerful solution in the form of the avif image format, which enables a further reduction in the file size of images. 50% and more savings compared to the webp format are the rule. Since the avif format is supported by all current browsers, it would be wasted potential if this image format were not used. The Microsoft Edge browser does not yet support the avif format, but avif support for this browser has already been announced.
With the avif image format you would have a very important tool to further improve the loading times. However, the LiteSpeed Cache Plugin does not support this format. As an alternative, switching to the numerous WP plugins for avif conversion that are now available is not a solution because they are consistently not cache-friendly. In addition, the recognition rate of the plugins known to us is usually not satisfactory.
The "KITT - AWR avif & webp replacement plugin" for Wordpress offers a way out of this dilemma. This plugin was specially developed for the LiteSpeed Cache plugin and replaces the standard webp replacement function of the cache plugin. True to the name of the KITT AWR plugin, this plugin enables webp and avif conversion and provides an optimization function for conventional image formats. Neither quic.cloud nor any other external service is required for this plugin, as the conversion takes place on our own server. This plugin also provides numerous LiteSpeed hacks, primarily to optimize and speed up the functionality of the cache plugin's built-in crawler.
You can find more and a detailed feature description on the download page.