As you may have noticed, I've been periodically updating old references since December.
There are currently 3 maintenance pages listing references which need to be updated. These are relatively easy tasks which anyone can do, and are a great way for new contributors to increase their edit count.
References which are missing various types of descriptions, including image and youtube references without captions, as well as raw links.
This is the most important of these three tasks, because adding descriptions improves the wiki. I have already updated several hundred of these over the past 5 months, and am I leaving it to others to add captions to images and descriptions to youtube links.
As well as being listed on that page, and categorised, references without descriptions are marked in red  in articles to draw attention to them.
References over 200 characters long, which should be changed to named references to reduce the size. Details about named references can be found on template:ref.
This is the least important of these three tasks, and is non-essential as it does not effect either reading or editing, just the length of the url when you click on a reference. I have updated many of the longest references over the past 5 months, and will continue to update them until there are no unnamed references longer than 200 characters.
As well as being being listed on that page, and categorised, unnamed references are marked with red exclamation mark ! in the reference section to draw attention to them.
- Old-style references - complete
Old-style image and youtube references, which must now use the image= and youtube= parameters. Details about these parameters can be found on template:ref.
Although updating these references shouldn't change the displayed information, this is still an essential task that must be completed as it will make the pages easy to edit, and the references easier to maintain.
- I have completed updating all of these, and all future uses of the old-style format will be automatically marked as broken.
As well as being listed on that page, old-style references are marked with red exclamation mark ! in the reference section to draw attention to them.
If anyone doesn't understand the documentation on template:ref, feel free to let me know what is unclear so I can update it.