failed to open window `xyz`

[Paddyk45]

i get the following errors when i start launch_eww:

failed to open window `background`

Caused by:
    No window named 'background' exists in config.
    This may also be caused by your config failing to load properly, please check for any other errors in that case.
failed to open window `profile`

Caused by:
    No window named 'profile' exists in config.
    This may also be caused by your config failing to load properly, please check for any other errors in that case.
failed to open window `system`

Caused by:
    No window named 'system' exists in config.
    This may also be caused by your config failing to load properly, please check for any other errors in that case.
failed to open window `clock`

Caused by:
    No window named 'clock' exists in config.
    This may also be caused by your config failing to load properly, please check for any other errors in that case.
failed to open window `uptime`

Caused by:
    No window named 'uptime' exists in config.
    This may also be caused by your config failing to load properly, please check for any other errors in that case.
failed to open window `music`

Caused by:
    No window named 'music' exists in config.
    This may also be caused by your config failing to load properly, please check for any other errors in that case.
failed to open window `github`
[...]

[p0ryae]

Did you find any solutions ???

[ubuntupunk]

You will notice the eww.xml file. The widgets are supposed to conform to the yuck format and should rather be declared in eww.yuck as per this link