After more testing I've narrowed it down to build 5099; build 5098 works perfectly, while the problem starts happening with 5099.
The problem happens with all themes.
I do have static html cache enabled but it doesn't need to be since I have excluded all pages (it was enabled in previous versions of the website and I just never disabled it), in fact I will just disable it now.
*disables it*
OK, with static html cache disabled, version 1.3.1.2 works perfectly. So I guess it's either a problem with static html cache or maybe the required syntax was changed from build 5098 to 5099?
I had the following in the plugin options input box:
`search.php/,contact.php/,image.php/,index.php/,album.php/`
In conclusion, disabling the static_html_cache plugin fixed the problem for me.
If there's any more testing you'd like me to do in order to identify why the plugin does that I would be happy to.