Hi,
We don’t know much about elementor, but we’ve seen many of our clients using it with our plugins without any problems. Honestly, I cannot tell you exactly what’s that output in your screen shot, it looks like raw text from a JSON encoded string, as it contains tab and new line feeds (“\t” and “\n”).
It may be possible that your page builder plugin is unable to convert a JSON encoded string for a live preview, but you will see that the result will work just fine.
Regarding the front-end: the warning message (it’s not an error) is not a consequence of the raw text in your first screen shot, it is rather something related to the configuration of your Theme or plugins. Basically, Vik Booking sends cookies to the browser, but such cookies cannot be sent, and a warning message will be triggered by your PHP installation, if the “headers” are started before the execution of Vik Booking.
In short, cookies should be sent to the browser before any output, and Vik Booking does its best to make sure the cookie is sent during the earliest WordPress hook of the loading of the page, when no other plugins or Theme should have sent nothing to the output for your browser.
Honestly, this is not the first time our clients are informing us of these conflicts, but they are not caused by our plugin, which is already doing everything correctly, and at the right time. This must be some other plugin that is interfering, but the good thing is that this is not an error, but rather a warning message that could be turned off for your installation. Nothing to be worried about as Vik Booking uses JavaScript to send cookies when your server (PHP) is unable to set them.
We are probably going to do something with the next updates of Vik Booking to just suppress this warning message, but the point is that in your case some other plugins are breaking the PHP headers at a time when they should be fully intact and usable by any plugin. In the next updates of Vik Booking we will just be preventing any possible conflicts with third party plugins or themes, but we want to clarify that the issue is not with Vik Booking as the PHP warning message suggests.
In the meantime, since that warning message is not going to cause any troubles at all, we suggest to turn off the error reporting in your installation, or at least to display only errors, not Warning messages of PHP.
We hope this helps.
The VikWP Team
