Okay, finally solved this, and it was a bit of a journey. First of all, I had to switch to the correct version of Java for thinkorswim desktop to work: Azul’s Zulu OpenJDK 11 using the following commands:
$ sudo dnf install -y https://cdn.azul.com/zulu/bin/zulu-repo-1.0.0-1.noarch.rpm
$ sudo dnf install zulu11-jdk
Then configure to default to the correct version:
$ sudo alternatives --config java
There are 2 programs which provide ‘java’.
Selection Command
*+ 1 java-17-openjdk.x86_64 (/usr/lib/jvm/java-17-openjdk-17.0.2.0.8-7.fc36.x86_64/bin/java)
2 /usr/lib/jvm/zulu11/bin/java
Enter to keep the current selection[+], or type selection number:
Press 2 (in this case) and then press ENTER. Double check that the Azul JDK is the primary:
$ java --version
openjdk 11.0.14.1 2022-02-08 LTS
OpenJDK Runtime Environment Zulu11.54+25-CA (build 11.0.14.1+1-LTS)
OpenJDK 64-Bit Server VM Zulu11.54+25-CA (build 11.0.14.1+1-LTS, mixed mode)
And , finally, here is the kicker: In order for the program to remain visible when running, I needed to configure GNOME to use Xorg. I accomplished this on the Fedora sign-on screen, by selecting the “gear icon” and choosing “GNOME on Xorg.”
Also, there are ways to add a “desktop entry” to start the program. If anyone needs advice on this, let me know. . .