diff --git a/chrome/content/zotero/xpcom/schema.js b/chrome/content/zotero/xpcom/schema.js
index 11cf5f28e..4783758e4 100644
--- a/chrome/content/zotero/xpcom/schema.js
+++ b/chrome/content/zotero/xpcom/schema.js
@@ -35,6 +35,10 @@ Zotero.Schema = new function(){
 	var _schemaUpdateDeferred = Zotero.Promise.defer();
 	this.schemaUpdatePromise = _schemaUpdateDeferred.promise;
 	
+	// If updating from this userdata version or later, don't show "Upgrading database…" and don't make
+	// DB backup first. This should be set to false when breaking compatibility or making major changes.
+	const minorUpdateFrom = 95;
+	
 	var _dbVersions = [];
 	var _schemaVersions = [];
 	// Update when adding _updateCompatibility() line to schema update step
@@ -131,9 +135,10 @@ Zotero.Schema = new function(){
 		);
 		
 		var schemaVersion = yield _getSchemaSQLVersion('userdata');
+		options.minor = minorUpdateFrom && userdata >= minorUpdateFrom;
 		
-		// If upgrading userdata, make backup of database first
-		if (userdata < schemaVersion) {
+		// If non-minor userdata upgrade, make backup of database first
+		if (userdata < schemaVersion && !options.minor) {
 			yield Zotero.DB.backupDatabase(userdata, true);
 		}
 		else if (integrityCheck) {
@@ -1909,7 +1914,7 @@ Zotero.Schema = new function(){
 		Zotero.debug('Updating user data tables from version ' + fromVersion + ' to ' + toVersion);
 		
 		if (options.onBeforeUpdate) {
-			let maybePromise = options.onBeforeUpdate()
+			let maybePromise = options.onBeforeUpdate({ minor: options.minor });
 			if (maybePromise && maybePromise.then) {
 				yield maybePromise;
 			}
@@ -2449,6 +2454,12 @@ Zotero.Schema = new function(){
 			else if (i == 95) {
 				yield Zotero.DB.queryAsync("DELETE FROM publicationsItems WHERE itemID NOT IN (SELECT itemID FROM items WHERE libraryID=1)");
 			}
+			
+			else if (i == 96) {
+				yield Zotero.DB.queryAsync("REPLACE INTO fileTypeMIMETypes VALUES(7, 'application/vnd.ms-powerpoint')");
+			}
+			
+			// If breaking compatibility or doing anything dangerous, clear minorUpdateFrom
 		}
 		
 		yield _updateDBVersion('userdata', toVersion);
diff --git a/chrome/content/zotero/xpcom/zotero.js b/chrome/content/zotero/xpcom/zotero.js
index 3da407126..5a7e3a760 100644
--- a/chrome/content/zotero/xpcom/zotero.js
+++ b/chrome/content/zotero/xpcom/zotero.js
@@ -618,7 +618,8 @@ Services.scriptloader.loadSubScript("resource://zotero/polyfill.js");
 			
 			try {
 				var updated = yield Zotero.Schema.updateSchema({
-					onBeforeUpdate: () => {
+					onBeforeUpdate: (options = {}) => {
+						if (options.minor) return;
 						try {
 							Zotero.showZoteroPaneProgressMeter(
 								Zotero.getString('upgrade.status')
diff --git a/resource/schema/system.sql b/resource/schema/system.sql
index d589d087f..eaad2b52f 100644
--- a/resource/schema/system.sql
+++ b/resource/schema/system.sql
@@ -1223,6 +1223,7 @@ INSERT INTO "fileTypeMIMETypes" VALUES(6, 'application/vnd.oasis.opendocument.te
 INSERT INTO "fileTypeMIMETypes" VALUES(7, 'application/powerpoint');
 INSERT INTO "fileTypeMIMETypes" VALUES(7, 'application/vnd.oasis.opendocument.presentation');
 INSERT INTO "fileTypeMIMETypes" VALUES(7, 'application/x-kpresenter');
+INSERT INTO "fileTypeMIMETypes" VALUES(7, 'application/vnd.ms-powerpoint');
 
 INSERT INTO "syncObjectTypes" VALUES(1, 'collection');
 INSERT INTO "syncObjectTypes" VALUES(2, 'creator');
diff --git a/resource/schema/userdata.sql b/resource/schema/userdata.sql
index 74c01eb65..034fd9bd0 100644
--- a/resource/schema/userdata.sql
+++ b/resource/schema/userdata.sql
@@ -1,4 +1,4 @@
--- 95
+-- 96
 
 -- Copyright (c) 2009 Center for History and New Media
 --                    George Mason University, Fairfax, Virginia, USA