This page lists the incompatible changes to the style scheme file format.
  The <author> tags are no longer supported, so you should
  remove them.
  The support for the parent-scheme attribute has been removed. It
  was unused. If you relied on it, copy and adapt the content of the parent
  scheme.
  The support for the line-background attribute (for the
  <style> tag) has been removed.
  You need to add the kind attribute (for light/dark), a new
  mandatory attribute.
  The version attribute of the <style-scheme>
  element is no longer supported, so you should remove it.
The parser is now a bit more strict, check if there are warning messages printed in the terminal if a style scheme fails to load.
  The background-pattern feature has been removed from the library. As such,
  a <style> tag with the name background-pattern
  is no longer taken as a special value (but it's not an error to keep it).