For this regex pattern, I need to match several different types of items:
1. Email addresses: with specific formats including '+' and '.' in usernames
2. URLs: with http, https, and sftp protocols
3. Version strings: in various formats with hyphens, dots, and alpha/beta/rc designations
4. Color codes: from short #fff to long #12345678 formats
5. Version numbers: simple and complex formats

To create a regex that matches only these items and nothing else, I'll use alternation (|) to separate different patterns for each target. I'll carefully escape special characters that have meaning in regex (like '.', '+', etc.).

For each item:
- Email addresses: I'll use exact matching with escaped special characters
- URLs: I'll escape forward slashes and special characters
- Version strings: I'll match the exact text patterns
- Color codes: I'll match the # followed by the exact hex characters
- Version numbers: I'll match the exact number patterns

The resulting pattern uses alternation (|) to combine all these specific patterns, ensuring exact matches of only the targeted items.