50  Known Limitations

• OPALX is not documented as a drop-in implementation of every historical OPAL flavor. OPAL-CYCL and OPAL-MAP material is not part of this manual.
• Registered but regression-untested interfaces are identified as source-supported; that label does not claim regression coverage.
• Some physics chapters document recently implemented models whose interface may still change; these pages are marked experimental.
• Backend support must be checked for each new algorithm; successful serial execution does not establish GPU support.
• Hard-edge fields and active elements shorter than a few integration steps can create numerical splitting. Always check time-step convergence.

These limitations are documentation status, not a substitute for the issue tracker. Report unexpected implemented behavior with a reproducible case.