I am trying to set an option page to my custom theme.
Since I made it, the posts don’t appear anymore in the archive page, and when I want to edit the permalink structure in settings > permalinks, I have this kind of error appearing :
Warning: Cannot modify header information - headers already sent by (output started at .../wp-content/themes/oniris-theme/options/options-init.php:1) in .../wp-includes/pluggable.php on line 1196
If I refresh the page, everything is okay.
Before giving all the code of my options-init.php template, is there any tip to fix or to find the issue ?