OpenProject seems to be an impressive well designed product. But there is something I think could be improved for a better user experience. Right now the work package IDs are monotonically increasing numbers.
This has a few drawbacks:

• The number seems to imply an ordering that is not true. In daily work packages are typically not created with a strict order in mind.
• The number seems to imply an importance. Shorter numbers are easier to remember and seem to imply higher importance. This is typically not the case.
• Using only decimal digits leads to longer numbers than using e.g. hex

My proposal is to use something similar to git hashes. In projects with only a few work packages only the first maybe 4 characters are enough to be unique. In larger projects longer prefixes can be used.