diff --git a/editor.css b/editor.css
new file mode 100644
index 0000000..83d2218
--- /dev/null
+++ b/editor.css
@@ -0,0 +1,25 @@
+.highlight-term {
+    background-color: lightgreen;
+}
+
+.relevant-density {
+    margin-top: 10px;
+    font-weight: bold;
+}
+
+.term-frequency {
+    margin-top: 5px;
+    padding: 3px;
+    display: inline-block;
+    border-radius: 4px;
+    margin-right: 2px;
+    margin-bottom: 2px;
+}
+
+.term-frequency[style*="lightgreen"] {
+    background-color: lightgreen;
+}
+
+.term-frequency[style*="lightred"] {
+    background-color: lightcoral;
+}
diff --git a/editor.js b/editor.js
new file mode 100644
index 0000000..9bab9ba
--- /dev/null
+++ b/editor.js
@@ -0,0 +1,308 @@
+const { PluginSidebar } = wp.editPost;
+const { TextareaControl, Button, ToggleControl } = wp.components;
+const { withSelect, withDispatch, subscribe } = wp.data;
+const selectData = wp.data.select;
+const { createElement: termsHighlighterEl, useState, useEffect } = wp.element;
+const { compose } = wp.compose;
+
+const TERMS_SPLIT_REGEX = /\s*,\s*|\s*\n\s*/;
+
+const computeRelevantDensity = (content, termsArray) => {
+    const contentWords = content.split(/\s+/);
+    const totalWords = contentWords.length;
+    let termCount = 0;
+
+    termsArray.forEach(term => {
+        const regex = new RegExp("\\b" + term + "\\b", "gi");
+        const matches = content.match(regex);
+        termCount += (matches ? matches.length : 0);
+    });
+
+    return (termCount / totalWords) * 100;
+};
+
+const computeRelevantDensityForHeadings = (blocks, termsArray) => {
+    let contentWords = [];
+
+    blocks.forEach(block => {
+        if (block.name === 'core/heading') {
+            contentWords = contentWords.concat(block.attributes.content.split(/\s+/));
+        }
+    });
+
+    if (!contentWords.length) return 0;
+
+    const totalWords = contentWords.length;
+    let termCount = 0;
+
+    termsArray.forEach(term => {
+        const regex = new RegExp("\\b" + term + "\\b", "gi");
+        termCount += contentWords.join(' ').match(regex)?.length || 0;
+    });
+
+    return (termCount / totalWords) * 100;
+};
+
+const displayRelevantDetails = (content, terms, sortType, showUnusedOnly) => {
+    if (!terms) return;
+
+    const searchTermInput = document.querySelector('.searchTermInput');
+    const currentSearchTerm = searchTermInput ? searchTermInput.value : "";
+
+    const termsArray = terms.split(TERMS_SPLIT_REGEX)
+                           .map(term => term.toLowerCase().trim())
+                           .filter(term => term !== "")
+                           .filter((term, index, self) => self.indexOf(term) === index);
+
+    const density = computeRelevantDensity(content, termsArray);
+    const blocks = selectData('core/block-editor').getBlocks();
+    const headingDensity = computeRelevantDensityForHeadings(blocks, termsArray);
+
+    let detailsHTML = '<div class="relevant-density">Relevant Density in Headings: ' + headingDensity.toFixed(2) + '%</div>' + '<div class="relevant-density">Relevant Density Overall: ' + density.toFixed(2) + '%</div>';
+
+    const termDetails = termsArray.map(term => {
+        const regex = new RegExp("\\b" + term + "\\b", "gi");
+        const matches = content.match(regex);
+        const count = (matches ? matches.length : 0);
+        return { term, count };
+    });
+
+    if (sortType === 'Count ascending') {
+        termDetails.sort((a, b) => a.count - b.count);
+    } else if (sortType === 'Alphabetically') {
+        termDetails.sort((a, b) => a.term.localeCompare(b.term));
+    } else {
+        termDetails.sort((a, b) => b.count - a.count);
+    }
+
+    const filteredDetails = showUnusedOnly ? termDetails.filter(detail => detail.count === 0) : termDetails;
+
+    filteredDetails.filter(detail => detail.term.toLowerCase().includes(currentSearchTerm.toLowerCase())).forEach(detail => {
+        const termElement = `<div class="term-frequency" style="background-color: ${detail.count > 0 ? 'lightgreen' : 'lightred'}" data-term="${detail.term}" onclick="copyToClipboard(event)">${detail.term} <sup>${detail.count}</sup></div>`;
+        detailsHTML += termElement;
+    });
+
+    const sidebarElement = document.querySelector('.relevant-density-optimizer .relevant-details');
+    if (sidebarElement) {
+        sidebarElement.innerHTML = detailsHTML;
+    }
+};
+
+const debounce = (func, wait) => {
+    let timeout;
+    return (...args) => {
+        clearTimeout(timeout);
+        timeout = setTimeout(() => func.apply(this, args), wait);
+    };
+};
+
+const debouncedDisplayRelevantDetails = debounce(displayRelevantDetails, 1000);
+
+const removeHighlighting = () => {
+    document.querySelectorAll(".editor-styles-wrapper .highlight-term").forEach(span => {
+        const parent = span.parentElement;
+        while (span.firstChild) {
+            parent.insertBefore(span.firstChild, span);
+        }
+        parent.removeChild(span);
+    });
+};
+
+const removeHighlightingFromContent = (content) => {
+    const tempDiv = document.createElement("div");
+    tempDiv.innerHTML = content;
+    tempDiv.querySelectorAll(".highlight-term").forEach(span => {
+        const parent = span.parentElement;
+        while (span.firstChild) {
+            parent.insertBefore(span.firstChild, span);
+        }
+        parent.removeChild(span);
+    });
+    return tempDiv.innerHTML;
+};
+
+const createHighlightPattern = (termsArray) => {
+    const escapedTerms = termsArray.map(term => term.replace(/[.*+?^${}()|[\]\\]/g, '\\$&'));
+    return new RegExp("\\b(" + escapedTerms.join('|') + ")\\b", "gi");
+};
+
+const highlightText = (node, pattern) => {
+    if (!node || !pattern) return;
+
+    if (node.nodeType === 3) {
+        let match;
+        let lastIndex = 0;
+        let fragment = document.createDocumentFragment();
+
+        while ((match = pattern.exec(node.nodeValue)) !== null) {
+            const precedingText = document.createTextNode(node.nodeValue.slice(lastIndex, match.index));
+            fragment.appendChild(precedingText);
+
+            const highlightSpan = document.createElement('span');
+            highlightSpan.className = 'highlight-term';
+            highlightSpan.textContent = match[0];
+            fragment.appendChild(highlightSpan);
+
+            lastIndex = pattern.lastIndex;
+        }
+
+        if (lastIndex < node.nodeValue.length) {
+            const remainingText = document.createTextNode(node.nodeValue.slice(lastIndex));
+            fragment.appendChild(remainingText);
+        }
+
+        if (fragment.childNodes.length > 0) {
+            node.parentNode.replaceChild(fragment, node);
+        }
+
+    } else if (node.nodeType === 1 && node.childNodes && !/(script|style)/i.test(node.tagName)) {
+        Array.from(node.childNodes).forEach(childNode => highlightText(childNode, pattern));
+    }
+};
+
+const highlightTerms = (termsArray, blocks = document.querySelectorAll(".editor-styles-wrapper .block-editor-block-list__block")) => {
+    const pattern = createHighlightPattern(termsArray);
+    requestAnimationFrame(() => {
+        removeHighlighting();
+        blocks.forEach(block => highlightText(block, pattern));
+    });
+};
+
+function copyToClipboard(event) {
+    const term = event.currentTarget.getAttribute('data-term');
+    navigator.clipboard.writeText(term);
+}
+
+const ImportantTermsComponent = compose([
+    withSelect(selectFunc => ({
+        metaFieldValue: selectFunc('core/editor').getEditedPostAttribute('meta')['_important_terms'],
+        content: selectFunc('core/editor').getEditedPostContent(),
+    })),
+    withDispatch(dispatch => ({
+        setMetaFieldValue: value => {
+            const editor = dispatch('core/editor');
+            let content = selectData('core/editor').getEditedPostContent();
+            content = removeHighlightingFromContent(content);
+            editor.editPost({ content: content });
+            editor.editPost({ meta: { _important_terms: value } });
+        }
+    }))
+])((props) => {
+    const [localTerms, setLocalTerms] = useState(props.metaFieldValue || "");
+    const [searchTerm, setSearchTerm] = useState("");
+    const [isHighlightingEnabled, toggleHighlighting] = useState(false);
+    const [sortType, setSortType] = useState("Count descending");
+    const [showUnusedOnly, setShowUnusedOnly] = useState(false);
+
+    const handleToggle = () => {
+        toggleHighlighting(!isHighlightingEnabled);
+        globalHighlightingState = !isHighlightingEnabled;
+        const terms = localTerms.split(TERMS_SPLIT_REGEX);
+        const sortedTerms = terms.sort((a, b) => b.length - a.length);
+        if (globalHighlightingState) {
+            highlightTerms(sortedTerms);
+        } else {
+            removeHighlighting();
+        }
+    };
+
+    useEffect(() => {
+    debouncedDisplayRelevantDetails(props.content, localTerms, sortType, showUnusedOnly);
+}, [props.content, searchTerm, localTerms, sortType, showUnusedOnly]);
+
+    useEffect(() => {
+    return () => {
+        debouncedDisplayRelevantDetails.cancel();
+    }
+}, []);
+
+    const saveTerms = () => {
+        let terms = localTerms.split(TERMS_SPLIT_REGEX);
+        terms = terms.map(term => term.toLowerCase().trim());
+        terms = terms.filter(term => term !== "");
+        terms = terms.filter(term => !term.includes('=='));
+        terms = [...new Set(terms)];
+        const cleanedTerms = terms.join('\n');
+        props.setMetaFieldValue(cleanedTerms);
+        setLocalTerms(cleanedTerms);
+    };
+
+    return termsHighlighterEl(
+        'div',
+        {},
+        termsHighlighterEl(TextareaControl, {
+            label: "Relevant Terms",
+            value: localTerms,
+            onChange: setLocalTerms
+        }),
+        termsHighlighterEl(ToggleControl, {
+            label: 'Highlight',
+            checked: isHighlightingEnabled,
+            onChange: handleToggle
+        }),
+        termsHighlighterEl(Button, {
+            isPrimary: true,
+            onClick: saveTerms
+        }, 'Update'),
+        termsHighlighterEl('br'),
+        termsHighlighterEl('br'),
+        termsHighlighterEl('select', {
+            value: sortType,
+            onChange: event => setSortType(event.target.value)
+            },
+        termsHighlighterEl('option', { value: 'Count descending' }, 'Count descending'),
+        termsHighlighterEl('option', { value: 'Count ascending' }, 'Count ascending'),
+        termsHighlighterEl('option', { value: 'Alphabetically' }, 'Alphabetically')
+        ),
+        termsHighlighterEl('br'),
+        termsHighlighterEl('br'),
+        termsHighlighterEl(ToggleControl, {
+            label: 'Unused only',
+            checked: showUnusedOnly,
+            onChange: () => setShowUnusedOnly(!showUnusedOnly)
+            }),
+        termsHighlighterEl('br'),
+        termsHighlighterEl('input', {
+            type: 'text',
+            placeholder: 'Search...',
+            value: searchTerm,
+            onChange: event => setSearchTerm(event.target.value),
+            className: 'searchTermInput'
+        }),
+        termsHighlighterEl('div', { className: 'relevant-density-optimizer' },
+            termsHighlighterEl('div', { className: 'relevant-details' })
+        )
+    );
+});
+
+wp.plugins.registerPlugin('relevant-density-optimizer', {
+    icon: 'awards',
+    render: () => termsHighlighterEl(PluginSidebar, {
+        name: "relevant-density-optimizer",
+        title: "Relevant Density Optimizer"
+    }, termsHighlighterEl(ImportantTermsComponent))
+});
+
+let globalHighlightingState = false;
+
+const handleEditorChange = () => {
+    const newContent = selectData('core/editor').getEditedPostContent();
+    const postMeta = selectData('core/editor').getEditedPostAttribute('meta') || {};
+    const terms = postMeta['_important_terms'] ? postMeta['_important_terms'].split('\n') : [];
+
+    if (newContent !== lastComputedContent || terms.join(',') !== lastComputedTerms) {
+        displayRelevantDetails(newContent, postMeta['_important_terms']);
+
+        if (globalHighlightingState) {
+            const sortedTerms = terms.sort((a, b) => b.length - a.length);
+            highlightTerms(sortedTerms);
+        }
+
+        lastComputedContent = newContent;
+        lastComputedTerms = terms.join(',');
+    }
+};
+
+const debouncedHandleEditorChange = debounce(handleEditorChange, 3000);
+
+subscribe(debouncedHandleEditorChange);
diff --git a/relevant-density-optimizer.php b/relevant-density-optimizer.php
new file mode 100644
index 0000000..59bbbef
--- /dev/null
+++ b/relevant-density-optimizer.php
@@ -0,0 +1,30 @@
+<?php
+/**
+ * Plugin Name: Relevant Density Optimizer
+ * Description: Highlight relevant terms in Gutenberg editor and optimize density.
+ * Author: Infinitnet
+ * Version: 1.6
+ */
+
+function rdo_enqueue_block_editor_assets() {
+    if (!wp_script_is('rdo-editor-js', 'enqueued')) {
+        wp_enqueue_script('rdo-editor-js', plugin_dir_url(__FILE__) . 'editor.js', array('wp-plugins', 'wp-edit-post', 'wp-element', 'wp-data', 'wp-compose', 'wp-components'), '1.1', true);
+    }
+
+    wp_enqueue_style('rdo-editor-css', plugin_dir_url(__FILE__) . 'editor.css', array(), '1.1');
+}
+
+add_action('enqueue_block_editor_assets', 'rdo_enqueue_block_editor_assets');
+
+function rdo_register_meta() {
+    register_meta('post', '_important_terms', array(
+        'show_in_rest' => true,
+        'single' => true,
+        'type' => 'string',
+        'auth_callback' => function() {
+            return current_user_can('edit_posts');
+        }
+    ));
+}
+
+add_action('init', 'rdo_register_meta');