I'm using PlantUML on WSL running Ubuntu 20.04.1 LTS and I have a problem with package backgrounds showing up as black, but only when the backgroundColor is already transparent.
Here's my configuration info:
$ uname -a
Linux DESKTOP-CHAOS 4.19.128-microsoft-standard #1 SMP Tue Jun 23 12:58:10 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 20.04.1 LTS
Release: 20.04
Codename: focal
$ java --version
openjdk 11.0.9.1 2020-11-04
OpenJDK Runtime Environment (build 11.0.9.1+1-Ubuntu-0ubuntu1.20.04)
OpenJDK 64-Bit Server VM (build 11.0.9.1+1-Ubuntu-0ubuntu1.20.04, mixed mode, sharing)
$ java -jar ~/java/plantuml.jar -version
PlantUML version 1.2020.20 (Sat Nov 21 05:02:45 EST 2020)
(GPL source distribution)
Java Runtime: OpenJDK Runtime Environment
JVM: OpenJDK 64-Bit Server VM
Default Encoding: UTF-8
Language: en
Country: null
PLANTUML_LIMIT_SIZE: 4096
Dot version: dot - graphviz version 2.43.0 (0)
Installation seems OK. File generation OK
Sample file:
$ cat sample.puml
@startuml
skinparam backgroundcolor transparent
skinparam packagebackgroundcolor transparent
skinparam style strictuml
package a {
class B
}
@enduml
$ java -jar ~/java/plantuml.jar -tsvg -charset UTF-8 sample.puml
Here's the resulting image (screenshot from inkscape)
If I remove skinparam backgroundcolor transparent everything is OK.