diff --git a/chrome/content/zotero/longTagFixer.xhtml b/chrome/content/zotero/longTagFixer.xhtml
index 0ece8650ad..fb29a62ea2 100644
--- a/chrome/content/zotero/longTagFixer.xhtml
+++ b/chrome/content/zotero/longTagFixer.xhtml
@@ -10,7 +10,6 @@
 	title="&zotero.sync.error;"
 	id="zotero-long-tag-fixer-window"
 	class="zotero-dialog"
-	width="600"
 	onload="Zotero_Long_Tag_Fixer.init()">
 <dialog
 	id="zotero-long-tag-fixer"
@@ -20,7 +19,7 @@
 		<html:h1>&zotero.sync.longTagFixer.followingTagTooLong;</html:h1>
 		<html:textarea id="zotero-old-tag" readonly="readonly" />
 		<label>&zotero.sync.longTagFixer.syncedTagSizeLimit;</label>
-		<label value="&zotero.sync.longTagFixer.splitEditDelete;"/>		
+		<label value="&zotero.sync.longTagFixer.splitEditDelete;"/>
 	</html:div>
 	<tabbox id="zotero-new-tag-actions">
 		<tabs>
@@ -30,7 +29,7 @@
 		</tabs>
 		<tabpanels>
 			<!-- Split -->
-			<vbox class="split-tab">
+			<tabpanel class="split-tab">
 				<hbox class="delimiter-input-wrap">
 					<label>&zotero.sync.longTagFixer.splitAtThe;</label>
 					<html:input
@@ -47,21 +46,21 @@
 						<button label="&zotero.general.selectAll;" oncommand="Zotero_Long_Tag_Fixer.selectAll()"/>
 					</div>
 				</hbox>
-			</vbox>
+			</tabpanel>
 			
 			<!-- Edit -->
-			<vbox class="edit-tab">
+			<tabpanel class="edit-tab">
 				<html:textarea id="zotero-new-tag-editor"/>
 				<html:div id="zotero-new-tag-characters">
 					<html:span id="zotero-new-tag-character-count" />
 					<html:span>&zotero.sync.longTagFixer.characters;</html:span>
 				</html:div>
-			</vbox>
+			</tabpanel>
 			
 			<!-- Delete -->
-			<vbox align="center" pack="center">
+			<tabpanel align="center" pack="center">
 				<label value="&zotero.sync.longTagFixer.tagWillBeDeleted;"/>
-			</vbox>
+			</tabpanel>
 		</tabpanels>
 	</tabbox>
 	<script src="include.js"/>
diff --git a/scss/components/_longTagFixer.scss b/scss/components/_longTagFixer.scss
index 51247137b1..5083bce669 100644
--- a/scss/components/_longTagFixer.scss
+++ b/scss/components/_longTagFixer.scss
@@ -2,6 +2,7 @@
 	padding: 20px;
 	font-size: 12px;
 	line-height: 1.333333333;
+	width: 600px;
 
 	h1 {
 		font-size: 13px;
@@ -20,6 +21,20 @@
 
 	tabpanels {
 		padding-top: 15px;
+		
+		tabpanel {
+			display: flex;
+			flex-direction: column;
+			width: 100%;
+			min-width: 0;
+			// prevent dialog from resizing when switching tabs or split character
+			min-height: 250px;
+
+			// fix min-width leaking to children for some reason causing weird glitch with checkboxes
+			* {
+				min-width: unset;
+			}
+		}
 
 		@include variant("#zotero-long-tag-fixer.is-long-tag") {
 			padding-top: 33px;
@@ -59,7 +74,7 @@
 
 	.split-tab {
 		.tag-list {
-			height: calc(8 * (1em + 10px));
+			max-height: calc(8 * (1em + 10px));
 			overflow-x: hidden;
 			padding: 8px;