And now some thoughts on the topic of custom tags, and whether they should be introduced at all.
The short answer is NO.
Now let's think about this topic - "Why?" . There is such a well-known Russian-language resource Habr, who remembers, it was originally also called Habrahabr. So they added a custom XML tag<cut> , which cut off the part of the article that was supposed to go in the preview, and the other part was hidden in the article preview. Thus, the user "removed the article under the cut" . At first glance, it is quite a good solution for the user to decide what should be in the article preview so that the article attracts attention in the site's news feed. On the other hand, how many times could you see comments: "Author, take the article under the cut!" . And here lies the main problem, in my opinion. After all, if an ordinary user needs to be constantly reminded of some basic functionality of the site in order for him to use it, then something is already wrong here.
Of course, Habr can afford to use such a tag, since he has developed and formed a community that monitors the implementation of such conventions. But if you are developing a small site that is not yet so famous, then maybe you should not add extra work to yourself? Think for yourself, because you will be the person who will constantly remind users to use<cut> . Either you will correct the articles yourself or write an automatic addition of a tag after a couple of paragraphs.
In fact, this is a waste of time. Personally, I regret that I wasted my time working on such functionality. After all, Django has a truncatewords_html tag in the template engine that allows you to truncate a certain number of words of content and closes all tags properly. In this case, even images can get into the preview of the article. So why not use a ready-made solution? After all, whoever really wants to show a picture in a preview will add it to the beginning of the article and everything will look as it should. In general, whoever really needs it will figure it out. And forcing the user to use such specific functionality for the most basic actions, like writing a post on the site, is not the best idea.
And what useless custom tags did you introduce?