diff --git a/ext/bg/js/database.js b/ext/bg/js/database.js
index 9e90e6de..fcf8ef3f 100644
--- a/ext/bg/js/database.js
+++ b/ext/bg/js/database.js
@@ -228,6 +228,21 @@ class Database {
         }
     }
 
+    async getTitlesWithSequences() {
+        if (!this.db) {
+            throw 'Database not initialized';
+        }
+
+        const titles = [];
+        await this.db.dictionaries.each(row => {
+            if (row.hasSequences) {
+                titles.push(row.title);
+            }
+        });
+
+        return titles;
+    }
+
     async importDictionary(archive, callback) {
         if (!this.db) {
             throw 'Database not initialized';
diff --git a/ext/bg/js/options.js b/ext/bg/js/options.js
index 2cb7dbec..4d18c166 100644
--- a/ext/bg/js/options.js
+++ b/ext/bg/js/options.js
@@ -203,7 +203,8 @@ function optionsSetDefaults(options) {
             popupOffset: 10,
             showGuide: true,
             compactTags: false,
-            compactGlossaries: false
+            compactGlossaries: false,
+            mainDictionary: ''
         },
 
         scanning: {
diff --git a/ext/bg/js/settings.js b/ext/bg/js/settings.js
index 37e5126e..36f2bdf9 100644
--- a/ext/bg/js/settings.js
+++ b/ext/bg/js/settings.js
@@ -25,6 +25,7 @@ async function formRead() {
     optionsNew.general.compactTags = $('#compact-tags').prop('checked');
     optionsNew.general.compactGlossaries = $('#compact-glossaries').prop('checked');
     optionsNew.general.resultOutputMode = $('#result-output-mode').val();
+    optionsNew.general.mainDictionary = $('#main-dictionary').val();
     optionsNew.general.audioSource = $('#audio-playback-source').val();
     optionsNew.general.audioVolume = parseFloat($('#audio-playback-volume').val());
     optionsNew.general.debugInfo = $('#show-debug-info').prop('checked');
@@ -62,9 +63,8 @@ async function formRead() {
         const title = dictionary.data('title');
         const priority = parseInt(dictionary.find('.dict-priority').val(), 10);
         const enabled = dictionary.find('.dict-enabled').prop('checked');
-        const main = dictionary.find('.dict-main').prop('checked');
         const allowSecondarySearches = dictionary.find('.dict-allow-secondary-searches').prop('checked');
-        optionsNew.dictionaries[title] = {priority, enabled, main, allowSecondarySearches};
+        optionsNew.dictionaries[title] = {priority, enabled, allowSecondarySearches};
     });
 
     return {optionsNew, optionsOld};
@@ -85,6 +85,13 @@ function formUpdateVisibility(options) {
         advanced.hide();
     }
 
+    const merge = $('.options-merge');
+    if (options.general.resultOutputMode === 'merge') {
+        merge.show();
+    } else {
+        merge.hide();
+    }
+
     const debug = $('#debug');
     if (options.general.debugInfo) {
         const temp = utilIsolate(options);
@@ -97,6 +104,29 @@ function formUpdateVisibility(options) {
     }
 }
 
+async function formMainDictionaryOptionsPopulate(options) {
+    const select = $('#main-dictionary').empty();
+
+    let titles = await utilDatabaseGetTitlesWithSequences();
+    titles = titles.filter(title => options.dictionaries[title].enabled);
+    const formOptionsHtml = [];
+    let mainDictionarySelected = false;
+    for (title of titles) {
+        if (options.general.mainDictionary === title) {
+            mainDictionarySelected = true;
+        }
+        formOptionsHtml.push(`<option value="${title}"${options.general.mainDictionary === title ? ' selected' : ''}>${title}</option>`);
+    }
+
+    if (!mainDictionarySelected) {
+        options.general.mainDictionary = '';
+    }
+
+    const notSelectedOptionHtml = `<option value=""${!mainDictionarySelected ? ' selected' : ''}>(Not selected)</option>`;
+
+    select.append($([notSelectedOptionHtml].concat(formOptionsHtml).join('')));
+}
+
 async function onFormOptionsChanged(e) {
     try {
         if (!e.originalEvent && !e.isTrigger) {
@@ -104,6 +134,7 @@ async function onFormOptionsChanged(e) {
         }
 
         const {optionsNew, optionsOld} = await formRead();
+        await formMainDictionaryOptionsPopulate(optionsNew);
         await optionsSave(optionsNew);
 
         formUpdateVisibility(optionsNew);
@@ -131,6 +162,7 @@ async function onReady() {
     $('#compact-tags').prop('checked', options.general.compactTags);
     $('#compact-glossaries').prop('checked', options.general.compactGlossaries);
     $('#result-output-mode').val(options.general.resultOutputMode);
+    $('#main-dictionary').val(options.general.mainDictionary);
     $('#audio-playback-source').val(options.general.audioSource);
     $('#audio-playback-volume').val(options.general.audioVolume);
     $('#show-debug-info').prop('checked', options.general.debugInfo);
@@ -172,6 +204,8 @@ async function onReady() {
         ankiErrorShow(e);
     }
 
+    await formMainDictionaryOptionsPopulate(options);
+
     formUpdateVisibility(options);
 }
 
@@ -243,18 +277,6 @@ function dictionaryGroupsSort() {
     dictGroups.append(dictGroupChildren);
 }
 
-function dictionarySetMain(e) {
-    const mainDictionary = $(e.target).closest('.dict-group');
-    const mainDictionaryTitle = mainDictionary.data('title');
-
-    $('.dict-group').each((index, element) => {
-        const dictionary = $(element);
-        if (dictionary.data('title') !== mainDictionaryTitle) {
-            dictionary.find('.dict-main').prop('checked', false);
-        }
-    });
-}
-
 async function dictionaryGroupsPopulate(options) {
     const dictGroups = $('#dict-groups').empty();
     const dictWarning = $('#dict-warning').hide();
@@ -265,14 +287,13 @@ async function dictionaryGroupsPopulate(options) {
     }
 
     for (const dictRow of dictRowsSort(dictRows, options)) {
-        const dictOptions = options.dictionaries[dictRow.title] || {enabled: false, priority: 0, main: false, allowSecondarySearches: false};
+        const dictOptions = options.dictionaries[dictRow.title] || {enabled: false, priority: 0, allowSecondarySearches: false};
         const dictHtml = await apiTemplateRender('dictionary.html', {
             title: dictRow.title,
             version: dictRow.version,
             revision: dictRow.revision,
             priority: dictOptions.priority,
             enabled: dictOptions.enabled,
-            main: dictOptions.main,
             allowSecondarySearches: dictOptions.allowSecondarySearches
         });
 
@@ -285,11 +306,6 @@ async function dictionaryGroupsPopulate(options) {
         dictionaryGroupsSort();
         onFormOptionsChanged(e);
     });
-
-    $('.dict-main').change(e => {
-        dictionarySetMain(e);
-        onFormOptionsChanged(e);
-    });
 }
 
 async function onDictionaryPurge(e) {
@@ -305,9 +321,11 @@ async function onDictionaryPurge(e) {
         await utilDatabasePurge();
         const options = await optionsLoad();
         options.dictionaries = {};
+        options.general.mainDictionary = '';
         await optionsSave(options);
 
         await dictionaryGroupsPopulate(options);
+        await formMainDictionaryOptionsPopulate(options);
     } catch (e) {
         dictionaryErrorShow(e);
     } finally {
@@ -333,10 +351,14 @@ async function onDictionaryImport(e) {
 
         const options = await optionsLoad();
         const summary = await utilDatabaseImport(e.target.files[0], updateProgress);
-        options.dictionaries[summary.title] = {enabled: true, priority: 0, main: false, allowSecondarySearches: false};
+        options.dictionaries[summary.title] = {enabled: true, priority: 0, allowSecondarySearches: false};
+        if (summary.hasSequences && !options.general.mainDictionary) {
+            options.general.mainDictionary = summary.title;
+        }
         await optionsSave(options);
 
         await dictionaryGroupsPopulate(options);
+        await formMainDictionaryOptionsPopulate(options);
     } catch (e) {
         dictionaryErrorShow(e);
     } finally {
diff --git a/ext/bg/js/templates.js b/ext/bg/js/templates.js
index e5640394..9f72e661 100644
--- a/ext/bg/js/templates.js
+++ b/ext/bg/js/templates.js
@@ -15,9 +15,7 @@ templates['dictionary.html'] = template({"1":function(container,depth0,helpers,p
     + ((stack1 = helpers["if"].call(alias1,(depth0 != null ? depth0.enabled : depth0),{"name":"if","hash":{},"fn":container.program(1, data, 0),"inverse":container.noop,"data":data})) != null ? stack1 : "")
     + "> Enable search</label>\n    </div>\n    <div class=\"checkbox options-advanced\">\n        <label><input type=\"checkbox\" class=\"dict-allow-secondary-searches\" "
     + ((stack1 = helpers["if"].call(alias1,(depth0 != null ? depth0.allowSecondarySearches : depth0),{"name":"if","hash":{},"fn":container.program(1, data, 0),"inverse":container.noop,"data":data})) != null ? stack1 : "")
-    + "> Allow secondary searches</label>\n    </div>\n    <div class=\"radio\">\n        <label><input type=\"radio\" class=\"dict-main\" "
-    + ((stack1 = helpers["if"].call(alias1,(depth0 != null ? depth0.main : depth0),{"name":"if","hash":{},"fn":container.program(1, data, 0),"inverse":container.noop,"data":data})) != null ? stack1 : "")
-    + "> Set as main dictionary</label>\n    </div>\n    <div class=\"form-group options-advanced\">\n        <label for=\"dict-"
+    + "> Allow secondary searches</label>\n    </div>\n    <div class=\"form-group options-advanced\">\n        <label for=\"dict-"
     + alias4(((helper = (helper = helpers.title || (depth0 != null ? depth0.title : depth0)) != null ? helper : alias2),(typeof helper === alias3 ? helper.call(alias1,{"name":"title","hash":{},"data":data}) : helper)))
     + "\">Result priority</label>\n        <input type=\"number\" value=\""
     + alias4(((helper = (helper = helpers.priority || (depth0 != null ? depth0.priority : depth0)) != null ? helper : alias2),(typeof helper === alias3 ? helper.call(alias1,{"name":"priority","hash":{},"data":data}) : helper)))
diff --git a/ext/bg/js/translator.js b/ext/bg/js/translator.js
index 5fcdea76..e6790fbf 100644
--- a/ext/bg/js/translator.js
+++ b/ext/bg/js/translator.js
@@ -57,12 +57,11 @@ class Translator {
 
     async findTermsMerged(text, dictionaries, alphanumeric) {
         const options = await apiOptionsGet();
-        const mainDictionary = Object.keys(options.dictionaries).filter(dict => options.dictionaries[dict].main).concat([''])[0];
         const secondarySearchTitles = Object.keys(options.dictionaries).filter(dict => options.dictionaries[dict].allowSecondarySearches);
         const titles = Object.keys(dictionaries);
         const {length, definitions} = await this.findTerms(text, dictionaries, alphanumeric);
 
-        const definitionsBySequence = dictTermsMergeBySequence(definitions, mainDictionary);
+        const definitionsBySequence = dictTermsMergeBySequence(definitions, options.general.mainDictionary);
 
         const definitionsMerged = [];
         const mergedByTermIndices = new Set();
@@ -73,7 +72,7 @@ class Translator {
 
             const result = definitionsBySequence[sequence];
 
-            const rawDefinitionsBySequence = await this.database.findTermsBySequence(Number(sequence), mainDictionary);
+            const rawDefinitionsBySequence = await this.database.findTermsBySequence(Number(sequence), options.general.mainDictionary);
             const definitionsByGloss = dictTermsMergeByGloss(result, rawDefinitionsBySequence);
 
             const secondarySearchResults = [];
diff --git a/ext/bg/js/util.js b/ext/bg/js/util.js
index 91b16e79..60f6452b 100644
--- a/ext/bg/js/util.js
+++ b/ext/bg/js/util.js
@@ -87,6 +87,10 @@ function utilDatabaseGetTitles() {
     return utilBackend().translator.database.getTitles();
 }
 
+function utilDatabaseGetTitlesWithSequences() {
+    return utilBackend().translator.database.getTitlesWithSequences();
+}
+
 function utilDatabasePurge() {
     return utilBackend().translator.database.purge();
 }
diff --git a/ext/bg/settings.html b/ext/bg/settings.html
index 408d5aab..8c457652 100644
--- a/ext/bg/settings.html
+++ b/ext/bg/settings.html
@@ -60,6 +60,11 @@
                     </select>
                 </div>
 
+                <div class="form-group options-merge">
+                    <label for="main-dictionary">Main dictionary</label>
+                    <select class="form-control" id="main-dictionary"></select>
+                </div>
+
                 <div class="form-group">
                     <label for="audio-playback-source">Audio playback source</label>
                     <select class="form-control" id="audio-playback-source">
diff --git a/tmpl/dictionary.html b/tmpl/dictionary.html
index 6b81c0c9..1dc04f0f 100644
--- a/tmpl/dictionary.html
+++ b/tmpl/dictionary.html
@@ -7,9 +7,6 @@
     <div class="checkbox options-advanced">
         <label><input type="checkbox" class="dict-allow-secondary-searches" {{#if allowSecondarySearches}}checked{{/if}}> Allow secondary searches</label>
     </div>
-    <div class="radio">
-        <label><input type="radio" class="dict-main" {{#if main}}checked{{/if}}> Set as main dictionary</label>
-    </div>
     <div class="form-group options-advanced">
         <label for="dict-{{title}}">Result priority</label>
         <input type="number" value="{{priority}}" id="dict-{{title}}" class="form-control dict-priority">