This issue is common to all RTL scripts, and vertically set scripts.

Adoption of logical keywords such as -start and -end, rather than -left and -right needs to be completed.

For margins, padding, block size, border colour, width & style, logical keywords such as margin-inline-start or margin-block-end are widely supported by major browsers in their simplest forms (such as those just mentioned). However, logical properties are not well supported in shorthands such as margin-block or margin-inline or the margin property. The lack of support for shorthands is significant, since they are expected to have high use.

Support for the margin shorthand is currently held up by a discussion about the appropriate syntax. See this CSS issue.

Other logical properties that are not widely supported include border radius, caption side, and float. Firefox does support border-radius and floats, but otherwise these are not supported.

See a set of test results.

These new values also need to be widely supported in editing applications.