Peculiar, hidden, and unsupported symbols in text compromise security, accessibility, and compatibility, reducing user experience and increasing vulnerability.

1. Security: Can mask malicious code.
2. Accessibility: Hard to interpret for assistive technologies.
3. Compatibility: May not display correctly across devices/browsers.

To guarantee to have a clean text free of peculiar, hidden and unsupported symbols, you can utilize the Google chrome address bar by following these instructions:

1. Copy the text.
2. Paste it into the address bar of your Google Chrome browser.
3. The address bar will automatically filter out any characters that are not allowed to be used in website addresses.
4. Copy the cleaned text from the search bar and use it in the Gmail address bar.

This method is effective because website URLs do not allow certain characters, ensuring that your subject line remains straightforward and error-free.