PHP regular expression to add rel="nofollow" to external links
39419
RegEx expression to find a href links and add NoFollow to them
47516
How do I stop mod_rewrite from appending links to url?
28700
Ban JSBin, Codepen, etc. links without code too
102499
Adding meta values to permalink
157495
RegEx to return 'href' attribute of 'link' tags only?
101189
Regular expression to extract URL from an HTML link
50811
Make user-inputted url into external link in rails
7336
What is the best regular expression to check if a string is a valid URL?
54707
How do I preserve the existing query string in a mod_rewrite rule
153237
Change post permalink to external URL from custom field
32878
Do “noopener noreferrer” links count as backlinks?
31700
Detect URLs in text with JavaScript
12584
Web designer's link back to own website (rel="designer" / rel="nofollow")
1849
RegEx match open tags except XHTML self-contained tags
96443
PHP regex for validating a URL
102388
hyperref adds extension to href
29242
Replace text with link to that text?