Blocking URL seems not working properly

[ThomAce]

URL Filter: /(.images/logo.png.)
Method: *
Text redirect URL: iisstart.png
Text type: plaintext

This gives no effect. I checked with Regex 101 and my regex seems good because I found what I'm looking for. Intentionally, I use in my HTML an unexisting reference to images/logo.png. So, the file is not there and I wanted to put instead another png file. Why is that not working? I tried all of the possibilities.

[dangkyokhoang]

If you want to match the exact name images/logo.png, a string filter should be enough. Text redirect URL must be a full URL as follow:

URL filter: images/logo.png
Text redirect: https://site.url/iisstart.png

Details: https://github.com/dangkyokhoang/man-in-the-middle#blocking-rules