picom-trans:tldr:cc4a6

This command is likely a configuration command for the picom compositor manager, used to control the transparency or opacity of a window with a specific name when it is running. Let's break it down:

• picom-trans is likely the executable command or script that manipulates the transparency or opacity settings in picom.
• --name is an option that specifies the name or title of the window to which the command's settings will be applied.
• ${Firefox} is a placeholder for the name of the window we want to modify. In this case, it is set as "Firefox", but it could be any other window name.
• --opacity is an option that determines the level of transparency or opacity the specified window will have.
• ${90} is another placeholder for a numerical value representing the opacity level. In this command, it is set as 90%, but it could be any other value between 0 and 100.

So, when this command is executed, it will instruct picom, the compositor manager, to change the opacity of the window named Firefox to 90% transparency.