I have a panel at the top of the screen in which there are several application buttons. Two of these are displayed as generic icons, and I wish to replace these with icons that I have found that are more indicative of the nature of the applications. I have done this before without difficulty, but I have not been able to do it now.
Both buttons are for bash script files. When I click on them, the scripts
do run and start their applications as expected, so the buttons
themselves work properly.
One of the icons is an .ico file and the other is a .png. Both are on the
desktop, and both have rw permissions for the user (which is me). When I
drag an icon toward the button-configuration window open, it becomes
accompanied by a "do not enter" symbol as soon as it gets into the
window, so that it will not drop. Clearly, I am doing something wrong or omitting something.