until such time as this issue is resolved: https://youtrack.jetbrains.com/issue/TBX-4599#focus=Comments-27-9828123.0-0

.bashrc

# custom Toolbox scripts
# export PATH="$PATH:$HOME/.local/share/JetBrains/Toolbox/scripts"
export PATH="$PATH:$HOME/tools/jetbrains-toolbox-wrappers/scripts"

update-jetbrains-scripts.sh

#!/usr/bin/env bash

destination_folder="$HOME/tools/jetbrains-toolbox-wrappers/scripts"

if [[ ! "${PATH//:/ }" =~ "$destination_folder" ]]; then
  echo "NOTE: custom scripts folder is not currently in PATH.."
fi

if [ ! -d "$destination_folder" ]; then
  mkdir -p "$destination_folder"
fi

for file in "$HOME/.local/share/JetBrains/Toolbox/scripts/"*; do
  filename=$(basename "$file")
  cp "$file" "$destination_folder/$filename"
  echo " &> /dev/null &" >> "$destination_folder/$filename"
done

echo "custom launcher scripts updated"
exit 0

IMPORTANT NOTE: this intentionally avoids directly modifying your .bashrc file or updating your PATH variable.. because if you don't use Bash, then you will obviously need to do something different here. these are one-time changes in your own environment, after which this script will "Just Work"(tm).

usage-wise, this script must be manually executed each time JetBrains ToolBox installs an IDE update, because that will result in a new shell launcher script being created in the $HOME/.local/share/JetBrains/Toolbox/scripts folder.

I may expand on this idea in the future, but for now this meets my personal needs, so anything more than this is dangerously close to over-engineering a (hopefully temporary) workaround.