IIS Rewrite - Condition for ignoring external URLs - iis

Question

I use the following rule to change the path of every image file to .webp. Except for the subdirectories typo3, fileadmin and upload. That works fine.
But the website also loads external images. These URLs shouldnt be changed to .webp
So I added
another condition
<add input="{HTTP_HOST}" pattern="mydomain.com" ignoreCase="true" />
In the rule test interface in IIS it works fine. I use an imagepath from my own domain. The rule test says the pattern fits. If I use an external image path, the pattern did not fit.
BUT if I load a page on my website with different images from different URLs all paths are changed to .webp and this means, that the external ones are not found (404).
How can I make this work?
<rule name="Webp" enabled="true">
<match url="(.+)\.(jpe?g|png)$" ignoreCase="true" />
<conditions logicalGrouping="MatchAll" trackAllCaptures="false">
<add input="{HTTP_ACCEPT}" pattern="image/webp" ignoreCase="false" />
<add input="{HTTP_HOST}" pattern="mydomain.com" />
<add input="{DOCUMENT_ROOT}/{R:0}.webp" matchType="IsFile" />
<add input="{REQUEST_URI}" pattern="typo3/" negate="true" />
<add input="{REQUEST_URI}" pattern="fileadmin/" negate="true" />
<add input="{REQUEST_URI}" pattern="uploads/" negate="true" />
</conditions>
<serverVariables>
<set name="ACCEPTS_WEBP" value="true" />
</serverVariables>
<action type="Rewrite" url="{R:0}.webp" appendQueryString="false" logRewrittenUrl="true" />
</rule>
</rules>
<outboundRules rewriteBeforeCache="true">
<rule name="jpg to webp" preCondition="ResponseIsHtml" enabled="true">
<conditions logicalGrouping="MatchAll" trackAllCaptures="false">
<add input="{HTTP_HOST}" pattern="mydomain.com" ignoreCase="true" />
<add input="{REQUEST_URI}" pattern="typo3/" negate="true" />
<add input="{REQUEST_URI}" pattern="fileadmin/" negate="true" />
<add input="{REQUEST_URI}" pattern="uploads/" negate="true" />
</conditions>

Answer 1

I have something new. The external images (and more information) are a response to an AJAX call like this from my own domain.
https://www.example.org:443/index.php?tx_jsdshopware_searchview%5B__referrer%2D%5B%40extension%5D=JsdShopware&tx_jsdshopware_searchview%5B__referrer%5D%5B%40controller%5D=SearchView&tx_jsdshopware_searchview%5B__referrer%5D%5B%40action%5D=list&tx_jsdshopware_searchview%5B__referrer%5D%5Barguments%5D=YTowOnt9af44e2e88d7b23601117be0ff9656fd98a839a38&tx_jsdshopware_searchview%5B__referrer%5D%5B%40request%5D=%7B%22%40extension%22%3A%22JsdShopware%22%2C%22%40controller%22%3A%22SearchView%22%2C%22%40action%22%3A%22list%22%7D2eb573bf2f44341434ca68abb64479da78fd5613&tx_jsdshopware_searchview%5B__trustedProperties%5D=%7B%22searchword%22%3A1%2C%22action%22%3A1%7D0a3b9fd37c893b374a4bb4c2daaa7dd2afa90ccc&tx_jsdshopware_searchview%5Bsearchword%5D=footest&type=4321&tx_jsdshopware_searchview%5Baction%5D=ajaxCall&_=13212131
Can I exclude the rewriting of the filenames my filtering for "ajax" ? I have no experience with these technology.