It's possible that these additional characters and numbers are specific to the particular HTML code you are analyzing and may be used for internal purposes by the website or application. They could be part of a custom markup or naming convention used by the developer or a specific framework or library employed in the project.
Without further context or knowledge of the specific codebase you are examining, it is challenging to determine their exact purpose or interpretation.
If you encounter any non-standard elements or syntax in HTML, it's crucial to refer to the original source code, documentation, or the developer who wrote the code to understand their intended use.
Regarding your interest in IoT security issues and solutions, you can find relevant information in the following link:
https://a-team.global/blog/main-iot-security-issues-and-solutions/. This blog post discusses key security challenges in the Internet of Things (IoT) space and offers insights into potential solutions to address them.