Inner cite delims not discharged in multi-cites

[moewew]

Consider the following MWE

\documentclass[british]{article}
\usepackage[T1]{fontenc}
\usepackage{babel}
\usepackage{csquotes}
\usepackage[backend=biber, style=ext-authoryear-comp]{biblatex}

\DeclareInnerCiteDelims{parencite}{\bibopenparen}{\bibcloseparen}
\DeclareOuterCiteDelims{parencite}{}{}

\addbibresource{biblatex-examples.bib}

\begin{document}
Lorem \parencite{sigfridsson}
ipsum \parencite{knuth:ct:a,knuth:ct:b}
dolor \parencites{knuth:ct:a}{knuth:ct:b}

Lorem \textcite{sigfridsson}
ipsum \textcite{knuth:ct:a,knuth:ct:b}
dolor \textcites{knuth:ct:a}{knuth:ct:b}
\end{document}

Lorem Sigfridsson and Ryde (1998) ipsum Knuth (1984, 1986) dolor Knuth (1984), 1986

Lorem Sigfridsson and Ryde (1998) ipsum Knuth (1984, 1986) dolor Knuth (1984, 1986)

See https://golatex.de/viewtopic.php?p=115992#p115992