Errors:
A “meta” element with an “http-equiv” attribute whose value is “X-UA-Compatible” must have a “content” attribute with the value “IE=edge”.
Using the “meta” element to specify the document-wide default language is obsolete. Consider specifying the language on the root element instead.
Attribute “type” not allowed on element “img” at this point.
Bad value “tel:0341 35575 80270” for attribute “href” on element “a”: Illegal character in scheme data: space is not allowed.
The element “a” must not appear as a descendant of the “button” element.
Bad value “” for attribute “target” on element “a”: Browsing context name must be at least one character long.
Attribute “target” not allowed on element “button” at this point.
An “img” element must have an “alt” attribute, except under certain conditions. For details, consult guidance on providing text alternatives for images.
Attribute “placeholder” not allowed on element “select” at this point.
Bad value “dest-optgroup-Alle Reiseziele” for attribute “id” on element “optgroup”: An ID must not contain whitespace.
Bad value “dest-optgroup-Top Reiseziele” for attribute “id” on element “optgroup”: An ID must not contain whitespace.
Bad value “dest-optgroup-nach Entfernung” for attribute “id” on element “optgroup”: An ID must not contain whitespace.
Duplicate ID “idestflat”.
Bad value “depAirport-optgroup-Alle Flughäfen” for attribute “id” on element “optgroup”: An ID must not contain whitespace.
Bad value “depAirport-optgroup-Tschechische Republik” for attribute “id” on element “optgroup”: An ID must not contain whitespace.
Bad value “depAirport-optgroup-Vereinigte Arabische Emirate” for attribute “id” on element “optgroup”: An ID must not contain whitespace.
Element “div” not allowed as child of element “label” in this context. (Suppressing further errors from this subtree.)
Duplicate ID “duration”.
Attribute “for” not allowed on element “span” at this point.
Bad character “ ” after “<”. Probable cause: Unescaped “<”. Try escaping it as “<”.
Attribute “placeholder” is only allowed when the input type is “email”, “number”, “password”, “search”, “tel”, “text”, or “url”.
Bad value “” for attribute “id” on element “div”: An ID must not be the empty string.
Element “div” not allowed as child of element “span” in this context. (Suppressing further errors from this subtree.)
Element “dd” not allowed as child of element “span” in this context. (Suppressing further errors from this subtree.)
Element “dt” not allowed as child of element “span” in this context. (Suppressing further errors from this subtree.)
Element “form” not allowed as child of element “ul” in this context. (Suppressing further errors from this subtree.)
Duplicate ID “”.
Bad value “” for attribute “id” on element “form”: An ID must not be the empty string.
Bad value “” for attribute “action” on element “form”: Must be non-empty.
Bad value “” for attribute “id” on element “span”: An ID must not be the empty string.
Element “p” not allowed as child of element “label” in this context. (Suppressing further errors from this subtree.)
Element “input” not allowed as child of element “ul” in this context. (Suppressing further errors from this subtree.)
Bad value “” for attribute “target” on element “form”: Browsing context name must be at least one character long.
Element “style” not allowed as child of element “body” in this context. (Suppressing further errors from this subtree.)
The value of the “for” attribute of the “label” element must be the ID of a non-hidden form control.
Warnings:
Consider avoiding viewport values that prevent users from resizing documents.
Section lacks heading. Consider using “h2”-“h6” elements to add identifying headings to all sections.
The first occurrence of ID “idestflat” was here.
The “date” input type is not supported in all browsers. Please be sure to test, and consider using a polyfill.
The first occurrence of ID “duration” was here.
The first occurrence of ID “” was here.
The “type” attribute is unnecessary for JavaScript resources.
This document appears to be written in German. Consider adding “lang="de"” (or variant) to the “html” start tag.
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