To set transparency for a signature or any other object in LibreOffice

 To set transparency for a signature or any other object in LibreOffice, follow these steps:

Impress or Draw (for images):

Click Tools > Color Replacer.

In the dialogue that opens, click the Pipette.

Select the part of the image you want to replace.

Click the part of the image with the yellow background.

Keep the selection as Transparent or choose another color.

Click the Replace button and then close the dialogue.

Draw (for signatures):

To remove the signature, draw a free-form line over it.

Select both the line and the image.

Click Shape > Subtract.

If you want a clean signature:

Create a new signature without attachments.

Set the background to transparent.

If you have only one template with the signature, you might need a third-party image editor like GIMP to achieve transparency1.

Remember that LibreOffice is primarily a vector graphic editor, not a pixel graphic editor. For more complex image editing tasks, consider using dedicated tools like GIMP, Krita, or paint.NET1.