diff --git a/src/Tool-ExternalBrowser/ExternalBrowser.class.st b/src/Tool-ExternalBrowser/ExternalBrowser.class.st
index 2e2e0be407c..0b2b6b1fd56 100644
--- a/src/Tool-ExternalBrowser/ExternalBrowser.class.st
+++ b/src/Tool-ExternalBrowser/ExternalBrowser.class.st
@@ -87,7 +87,7 @@ ExternalBrowser class >> serviceBrowseCode [
 		selector: #browseStream:
 		description: 'Open a "file-contents browser" on this file, allowing you to view and selectively load its code'
 		buttonLabel: 'Code')
-		argumentGetter: [ :file| file readOnlyStream ]
+		argumentGetter: [ :file| file readStream]
 ]
 
 { #category : #'System-FileRegistry' }
diff --git a/src/Tool-ExternalBrowser/ExternalBrowserTest.class.st b/src/Tool-ExternalBrowser/ExternalBrowserTest.class.st
new file mode 100644
index 00000000000..1f1afe29a01
--- /dev/null
+++ b/src/Tool-ExternalBrowser/ExternalBrowserTest.class.st
@@ -0,0 +1,85 @@
+Class {
+	#name : #ExternalBrowserTest,
+	#superclass : #TestCase,
+	#instVars : [
+		'initialWindows',
+		'file'
+	],
+	#category : #'Tool-ExternalBrowser-Test'
+}
+
+{ #category : #running }
+ExternalBrowserTest >> assert: serviceProvider dropFileWithSuffix: suffix [
+	| allMatchingServices service |
+	allMatchingServices := serviceProvider fileReaderServicesForFile: file pathString suffix: suffix.
+	self deny: allMatchingServices isEmpty.
+	service := allMatchingServices anyOne.
+	self shouldnt: [service performServiceFor: file] raise: MessageNotUnderstood.
+
+]
+
+{ #category : #running }
+ExternalBrowserTest >> classNameForTest [
+	^#MyWonderfulClass
+]
+
+{ #category : #running }
+ExternalBrowserTest >> fileForTestContent [
+	^'''From Pharo7.0.0rc1 of 4 December 2018 [Build information: Pharo-7.0.0+rc1.build.1435.sha.4cd23cf7be1a90c7c52e9f8786860a6290b7c2a6 (64 Bit)] on 5 December 2018 at 9:30:34.922838 am''!
+Object subclass: #', self classNameForTest,'
+	instanceVariableNames: ''some iv''
+	classVariableNames: ''''
+	poolDictionaries: ''''
+	category: #MyCategory!
+!', self classNameForTest,' commentStamp: ''NouryBouraqadi 12/4/2018 17:19'' prior: 0!
+My unique and explicit comment!
+
+
+!', self classNameForTest,' methodsFor: ''protocol'' stamp: ''NouryBouraqadi 12/4/2018 17:12''!
+myMethod
+	! !
+'
+]
+
+{ #category : #running }
+ExternalBrowserTest >> fileNameForTest [
+	^ 'fileForExternalBrowserTest'
+]
+
+{ #category : #running }
+ExternalBrowserTest >> initFileWithSuffix: suffix [
+	file := FileSystem workingDirectory / self fileNameForTest, '.', suffix.
+	file
+		writeStreamDo: [ :stream | stream nextPutAll: self fileForTestContent ].
+	initialWindows := World windowsSatisfying: [: each| true ].
+]
+
+{ #category : #running }
+ExternalBrowserTest >> setUp [
+	super setUp.
+	initialWindows := World windowsSatisfying: [: each| true ].
+]
+
+{ #category : #running }
+ExternalBrowserTest >> tearDown [ 
+	| newWindows |
+	super tearDown.
+	file deleteIfAbsent: [ ].
+	Smalltalk at: self classNameForTest  ifPresent: [ : cl | cl removeFromSystem ].
+	newWindows := World windowsSatisfying: [ : each | (initialWindows includes: each) not ].
+	newWindows do: #delete.
+]
+
+{ #category : #running }
+ExternalBrowserTest >> testDropChangeFile [
+	self initFileWithSuffix: 'changes'.
+	self assert: ExternalChangesBrowser dropFileWithSuffix: 'changes'
+
+]
+
+{ #category : #running }
+ExternalBrowserTest >> testDropStFile [
+	self initFileWithSuffix: 'st'.
+	self assert: ExternalBrowser dropFileWithSuffix: 'st'
+
+]
diff --git a/src/Tool-ExternalBrowser/ExternalChangesBrowser.class.st b/src/Tool-ExternalBrowser/ExternalChangesBrowser.class.st
index b890a32e7c1..20f0b76eb7b 100644
--- a/src/Tool-ExternalBrowser/ExternalChangesBrowser.class.st
+++ b/src/Tool-ExternalBrowser/ExternalChangesBrowser.class.st
@@ -114,7 +114,7 @@ ExternalChangesBrowser class >> serviceBrowseCSOrSTFile [
 		selector: #openOnStream:
 		description: 'Open a changelist tool on this file'
 		buttonLabel: 'Changes')
-		argumentGetter: [ :stream | stream readOnlyStream ]
+		argumentGetter: [ :stream | stream readStream ]
 ]
 
 { #category : #'file service' }