I believe you are all familiar with this attribute. I won’t go into details about the introduction of this attribute here. Baidu, there are too many introductions about it. I will make a record here, that is, through the link on the web page. When tagging a CSS file, the stylesheet attribute cannot be omitted. If omitted, the browser will not be able to parse the CSS style sheet properly.
Today I was originally using the bootstrap framework to write a mobile page, but there was a framework that had no style when I finished writing it. I debugged it for a long time and didn’t find anything wrong. Finally, I started to follow up and found the result. I found that the link tag lacked the stylesheet attribute, and then added the stylesheet attribute, and the effect was normal. I was not sure if it was because of the use of the bootstrap framework that I had to add the stylesheet attribute. Finally, I rewrote a test page without using anything in bootstrap. When the stylesheet was not added, the browser still could not parse the style file. After adding it, it is normal. The html versions I tested include html5, xhtml1.0, and html4.01.
If there are others, please feel free to add them in time.