v0.13.19

Sandbox

• Fixed a bug that prevented the ledger from loading transactions with empty workflow ids.
• Fixed internal shutdown order to avoid dead letter warnings when
  stopping Sandbox/Ledger API Server. See issue
  #1886.

DAML Studio

• Added a new command for visualizing a project in the IDE.
• Print stack trace when a scenario fails.
• Various memory leaks have been fixed so long-running sessions should
  no longer show a significant increase in memory usage.

DAML Compiler

• The --project-root option now works properly with relative paths
  in daml build.
• Support generic template declarations and instances. Documentation
  for generic templates is still being worked on.
• The --dump-pom flag from damlc package has been removed as
  packaging has not relied on POM files for a while.

Navigator

• {"None": {}} and {"Some": value}, where previously accepted, are no longer supported or used for DAML Optional values.
  Instead, for simple cases, use the plain value for Some, and null for None.
  See issue #2361 for other cases.

HTTP JSON API

• A new, more intuitive JSON format for DAML values is supported.
  See issue #2361.