GitLab.com integrated PlantUML version is too old to render some diagrams properly

Summary

The GitLab.com integrated PlantUML version - 1.2021.7 - is too old to support some useful features.

Steps to reproduce

  1. Create a Markdown (.md) file, or open an issue/MR/whatever which description could be written in Markdown;
  2. Create a PlantUML WBS diagram inside this Markdown document;
  3. Try to create a multiline node in this WBS diagram:
```plantuml
@startwbs
* Initial node
** Here is an example of single-line node
**:Here is an example
of multiline node;
@endwbs
```

which renders to

  1. PlantUML does not render properly the diagram, rather saying that there is a syntax error. Also note it says its version is (on 2021-10-07) 137 days old.

What is the current bug behavior?

PlantUML is not able to render correctly the diagram since the integrated version of GitLab.com is too old to parse correctly this new syntax.

What is the expected correct behavior?

PlantUML should render the diagram like this:

correct_diagram_screenshot

Output of checks

This bug happens on GitLab.com

Possible fixes

Upgrade PlantUML version to at least 1.2021.12 which is known to work correctly.

Non-related

Thank you for your work!