markdown 多个`:: selection`s oddity的规则集

Posted 2021-05-06

For some reason, selecting multiple `::selection`s with a ruleset doesn't work.  

This works:
```
::selection {
  background: red; 
}
::-moz-selection {
	background: red; 
}
```

But this doesn't:  
```
::selection,
::-moz-selection {
	background: red; 
}
```