I barely realize that my website was a mess when I post nginx load balancer article. It’s work fine at my localhost, but become a mess when I push to gitlab.
Then I check my blog using wappalyzer, gitlab has updated their hugo version to version 0.60 and I still using 0.58 at local. In 0.58, hugo using Blackfriday as markdown rendering engine, in version 0.60 they start using Goldmark. Differences is Goldmark mark html as unsafe element. The solution was easy, add this line at your config.toml (my config.toml located at root folder)
[markup]
[markup.goldmark]
[markup.goldmark.renderer]
unsafe = true
Source : gohugo.io-html code not working