Panel freezes when sub window appear in java program

[timik29]

I use IntelliJ software for development. And it's terrible when bottom panel freezes when appear some hints in java program.
I use oracle java 8

update-java-alternatives -l
java-1.11.0-openjdk-amd64 1101 /usr/lib/jvm/java-1.11.0-openjdk-amd64
java-8-oracle 1081 /usr/lib/jvm/java-8-oracle


sudo update-alternatives --config java
There are 2 choices for the alternative java (providing /usr/bin/java).

Selection Path Priority Status
------------------------------------------------------------
0 /usr/lib/jvm/java-11-openjdk-amd64/bin/java 1101 auto mode
1 /usr/lib/jvm/java-11-openjdk-amd64/bin/java 1101 manual mode
* 2 /usr/lib/jvm/java-8-oracle/jre/bin/java 1081 manual mode