Today I noticed that "Links To Your Site" in Google Webmaster Tools dropped from 2130 to 23, and from 122 domains to 11 domains. That's more than a 90% decrease!!
After some researching, I noticed that something similar happened in 2013 and it was due to a Google Technical problem. But that was 2 years ago and I haven't found any recent articles. What could have happened?
It's impossible that all the sites deleted links to my domain, because I own some of them and the links are still there, while they are not listed anymore in Webmaster Tools.
I recently made these modifications to my website:
Moved all the source code to CodeIgniter (tested and working with just some minor bugs to fix)
Optimized the website for mobile using Foundation
Introduced HTTPS and forced it to all my URLS
<link rel="canonical">from HTTP to HTTPS
Could one of these have been the cause of such behaviour? (Even if it doesn't look logical, because I made no changes on the domain). If not, what could have happened?