This is a checklist with solutions for 9 of the biggest failings I've found when debugging my client's websites ( I've been in web development and marketing since 2003 ).
— it's info that can help you make your website 2X more effective by locating the weak points so that you can quickly handle them.
And that makes the whole process of debugging your site much easier. Each point has instructions so you can easily start correcting them.
Read down a list of possible points that may be a bug and compare each point to what you have in place. If you find that one of the points is "out" with your website, then read the solution and correct it.