Why html work in fisddler and not in mail

Fiddler and Mail are two different applications that handle HTTP requests and responses in different ways, which can affect how HTML code is rendered. Here are some possible reasons why HTML might work in Fiddler but not in Mail:

  1. Rendering engine: Fiddler is a web debugging proxy that uses the Internet Explorer rendering engine to render HTML pages. This means that Fiddler uses the same rendering engine as Internet Explorer to display HTML content. On the other hand, Mail (e.g., Outlook, Gmail, etc.) uses its own rendering engine to display HTML emails. The rendering engines might have different interpretations of HTML code, leading to differences in how the HTML is rendered.
  2. HTML parsing: Fiddler allows you to inspect and modify HTTP requests and responses, which means it can parse HTML code in a more flexible way than Mail. Mail, on the other hand, has to parse HTML code in a more restrictive way to ensure security and prevent malicious code execution.
  3. CSS and JavaScript: Fiddler allows you to inspect and modify CSS and JavaScript code, which can affect how HTML is rendered. Mail, however, might not allow you to modify these code types or might have restrictions on how they are executed.
  4. Email client limitations: Mail clients like Outlook or Gmail have limitations on how they render HTML emails. For example, they might not support certain HTML tags, CSS styles, or JavaScript code. These limitations can cause HTML code to not work as expected in Mail.
  5. Character encoding: Fiddler and Mail might use different character encodings to render HTML content. For example, Fiddler might use UTF-8, while Mail might use ISO-8859-1. This can cause issues with special characters or non-ASCII characters in the HTML code.
  6. Security restrictions: Mail clients often have security restrictions in place to prevent malicious code execution. These restrictions can cause HTML code to not work as expected or might prevent certain HTML tags or attributes from being used.

To troubleshoot HTML issues in Mail, you can try the following:

  1. Check the Mail client's documentation for supported HTML tags and attributes.
  2. Use a simple HTML editor to create a test HTML page and see if it works in Mail.
  3. Check the HTML code for any errors or syntax issues.
  4. Try using a different Mail client or a web-based email service to see if the issue is specific to the current Mail client.

If you're still having issues, feel free to provide more details about the specific HTML code and the error message you're seeing, and I'll do my best to help you troubleshoot the issue!