Sometimes after you uninstall a Dreamweaver extension, you see a message that a file can't be found in the Configuration/Floaters directory. "The floater will not be shown." This is caused by Dreamweaver failing to remove an entry for the extension panel from your workspace file.
Assuming that you haven't created a custom workspace that includes the extension panel, the simple way to solve the problem is to open the Workspace menu, and select Reset Classic (or whatever the name of your workspace is). Alternatively, select Window > Workspace Layout > Reset (workspace name). The next time you open Dreamweaver, the message about the float should not appear.
If that doesn't fix the problem, you need to edit one or more files in your personal configuration folder.
<panelframe dock="floating" height="500" width="100" x="30" y="30">
<panelcontainer expanded="true" height="180" visible="false">
<panel height="180" id="ConvertToRGBA" unconstrainedheight="180" unconstrainedwidth="212" width="212"/>
</panelcontainer>
</panelframe>
After deleting the <panelframe> element(s) for the extension you uninstalled, the problem should go away.
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