I'm working on a site that contains passages in old spellings of the Luxembourgish language. This means that it contains an extreme assortment of weird diacritics, strangely placed apostrophes and mixtures of characters, in order to create the various "Umlauts" that the language contains. (Our grammar and orthography were standardized very late.)
My problem is that for some reason the letter û (u circumflex) is not accepted and throws an error however I enter it. I have tried to insert it in the Gutenberg editor, the WPBakery editor, even in HTML, both literally and as a HTML code (both û and ^ u don't work), but nothing works.
I always get a message that says: Updating failed. The response is not a valid JSON response.
In case it's important or the prior characters affect it in a weird way, the whole sentence is:
Éch hun dir ěwég Trei geschwûor.
In the above sentence, there are a multitude of weird characters, but only the û makes wordpress scream and throw a tantrum. Why?
Does Wordpress use this character as a placeholder for something? Or is it the server the site is hosted on? I've tried every way I know to insert that letter into the text and I am at a loss.
Thanks in advance.
EDIT:
Here is the JSON request it sends out and the response it gets to this request.
{"id":[[an id number]],"content":"<!-- wp:separator -->\n<hr class=\"wp-block-separator\"/>\n<!-- /wp:separator -->\n\n<!-- wp:heading {\"textAlign\":\"center\",\"level\":3} -->\n<h3 class=\"has-text-align-center\"><em>Onst Heemechtsland</em></h3>\n<!-- /wp:heading -->\n\n<!-- wp:separator -->\n<hr class=\"wp-block-separator\"/>\n<!-- /wp:separator -->\n\n<!-- wp:paragraph {\"style\":{\"color\":{\"text\":\"#808000\"}}} -->\n<p class=\"has-text-color\" style=\"color:#808000\"><em><strong>Werkinformationen:</strong></em></p>\n<!-- /wp:paragraph -->\n\n<p style=\"padding-left: 40px;\"><strong>Titel: </strong>Onst Heemechtsland</p>\n<p style=\"padding-left: 40px;\"><strong>Komponist: </strong>Laurent Menager</p>\n<p style=\"padding-left: 40px;\"><strong>Text:</strong> Jean Nicolas Moes</p>\n<p style=\"padding-left: 40px;\"><strong>Datum: </strong>Unbekannt</p>\n<p style=\"padding-left: 40px;\"><strong>Besetzung: </strong>TTBB a cappella</p>\n<p style=\"padding-left: 40px;\"><strong>Einordnung:</strong> weltliches Vokalwerk, Chorlied TTBB a cappella</p>\n<p style=\"padding-left: 40px;\"><strong>Textincipit:</strong> ,,Éch hun dir ěwég Trei geschwûor\"</p>\n\n<!-- wp:paragraph {\"style\":{\"color\":{\"text\":\"#808000\"}}} -->\n<p class=\"has-text-color\" style=\"color:#808000\"><strong><em>Materialbeschreibung:</em></strong></p>\n<!-- /wp:paragraph -->\n\n<p style=\"padding-left: 40px\"><strong>Typ: </strong>Edition: Partitur, Verlag Decker-Müllendorff, Luxembourg</p>\n<p style=\"padding-left: 40px\"><strong>Quellenart & Umfang:</strong> Partitur, 10 S.</p>\n<p style=\"padding-left: 40px\"><strong>Format: </strong>17,2 x 27,2 cm</p>\n<p style=\"padding-left: 40px\"><strong>Signatur:</strong> Archiv des Sang & Klang, O2</p>"}
<html><head><title>Request Rejected</title></head><body>The requested URL was rejected. Please consult with your administrator.<br><br>Your support ID is: [[a long id number]]<br><br><a href='javascript:history.back();'>[Go Back]</a></body></html>