I've stumbled on an activation error of the plugin, I'm developing and I can't seem to remove it. The error says "Plugin generate 2890 characters of unexpected output when activated". The purpose of my plugin is to view a banner at the website with information of an event happening. Both the banner and functionality works fine after the error message is shown.
My plugin is split into multiple files. I have the functionality in their seperate files and I have the view/HTML in another seperate file. I added an error log to the php script and it returns the HTML for the banner.
I have tried to turn the html into a Heredocs , but with no luck removing the error.
Do any of you have some advice on how to resolve the error of activation?
Thank you for your time.
Best regards Kristine