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diff --git a/src/templates/assets/javascripts/integrations/search/highlighter/index.ts b/src/templates/assets/javascripts/integrations/search/highlighter/index.ts
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+/*
+ * Copyright (c) 2016-2023 Martin Donath <martin.donath@squidfunk.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+import escapeHTML from "escape-html"
+
+import { SearchConfig } from "../config"
+
+/* ----------------------------------------------------------------------------
+ * Types
+ * ------------------------------------------------------------------------- */
+
+/**
+ * Search highlight function
+ *
+ * @param value - Value
+ *
+ * @returns Highlighted value
+ */
+export type SearchHighlightFn = (value: string) => string
+
+/**
+ * Search highlight factory function
+ *
+ * @param query - Query value
+ *
+ * @returns Search highlight function
+ */
+export type SearchHighlightFactoryFn = (query: string) => SearchHighlightFn
+
+/* ----------------------------------------------------------------------------
+ * Functions
+ * ------------------------------------------------------------------------- */
+
+/**
+ * Create a search highlighter
+ *
+ * @param config - Search configuration
+ *
+ * @returns Search highlight factory function
+ */
+export function setupSearchHighlighter(
+  config: SearchConfig
+): SearchHighlightFactoryFn {
+  // Hack: temporarily remove pure lookaheads and lookbehinds
+  const regex = config.separator.split("|").map(term => {
+    const temp = term.replace(/(\(\?[!=<][^)]+\))/g, "")
+    return temp.length === 0 ? "�" : term
+  })
+    .join("|")
+
+  const separator = new RegExp(regex, "img")
+  const highlight = (_: unknown, data: string, term: string) => {
+    return `${data}<mark data-md-highlight>${term}</mark>`
+  }
+
+  /* Return factory function */
+  return (query: string) => {
+    query = query
+      .replace(/[\s*+\-:~^]+/g, " ")
+      .trim()
+
+    /* Create search term match expression */
+    const match = new RegExp(`(^|${config.separator}|)(${
+      query
+        .replace(/[|\\{}()[\]^$+*?.-]/g, "\\$&")
+        .replace(separator, "|")
+    })`, "img")
+
+    /* Highlight string value */
+    return value => escapeHTML(value)
+      .replace(match, highlight)
+      .replace(/<\/mark>(\s+)<mark[^>]*>/img, "$1")
+  }
+}