When citing within the text, the citation appears within lines like so: |1| instead of within brackets like so: [1]. Within the bibliography, the citations appear correct. I have a hunch that there is a problem with the display, making the citations look like it's between lines because the serifs aren't displaying properly, but I can't figure out the problem.
Here is the preamble:
\documentclass[12pt,a4paper,bibtotoc]{scrreprt}
\usepackage[ngerman]{babel}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{csquotes}
\usepackage{blindtext}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{textcomp}
\usepackage{gensymb}
\usepackage{graphicx}
\usepackage{float}
\usepackage{siunitx}
\usepackage[onehalfspacing]{setspace} %1,5-facher Zeilenabstand
\usepackage{colortbl}
\usepackage{xcolor}
\restylefloat{table}
\graphicspath{{Bilder/}}
\usepackage[backend=biber,style=numeric]{biblatex}
\addbibresource{LiteraturBericht3.bib}
\newcommand{\chapterref}[1]{Kapitel~\ref{#1}}
\newcommand{\sectionref}[1]{Abschnitt~\ref{#1}}
\newcommand{\subsectionref}[1]{Unterabschnitt~\ref{#1}}
\newcommand{\equationref}[1]{Gl.~(\ref{#1})}
\newcommand{\figureref}[1]{Figur~\ref{#1}}
\newcommand{\tableref}[1]{Tabelle~\ref{#1}}
\def\SymbReg{\textsuperscript{\textregistered}}
\usepackage[breaklinks,pdfpagelabels,pdfstartview = FitH,bookmarksopen = true,bookmarksnumbered = true, colorlinks = false, urlbordercolor = {white}, linkbordercolor = {white}, citebordercolor = {white}, plainpages = false, hypertexnames = false, citecolor = black] {hyperref}
\usepackage[automark, headsepline, autooneside=false]{scrlayer-scrpage}
\pagestyle{scrheadings}
\automark{chapter}
\ihead{\headmark}
\ohead[\pagemark]{\pagemark}
\chead{}
\cfoot[]{}
\renewcommand*\chapterpagestyle{scrheadings}
And here are pictures of what I mean:
The citation within the text:
The citation within the bibliography, how I also would prefer them within the text, with square brackets: