diff --git a/app/src/main/java/com/github/shadowsocks/plugin/v2ray/CertificatePreferenceDialogFragment.kt b/app/src/main/java/com/github/shadowsocks/plugin/v2ray/CertificatePreferenceDialogFragment.kt
new file mode 100644
index 0000000..a1a18b1
--- /dev/null
+++ b/app/src/main/java/com/github/shadowsocks/plugin/v2ray/CertificatePreferenceDialogFragment.kt
@@ -0,0 +1,52 @@
+/*******************************************************************************
+ *                                                                             *
+ *  Copyright (C) 2019 by Max Lv <max.c.lv@gmail.com>                          *
+ *  Copyright (C) 2019 by Mygod Studio <contact-shadowsocks-android@mygod.be>  *
+ *                                                                             *
+ *  This program is free software: you can redistribute it and/or modify       *
+ *  it under the terms of the GNU General Public License as published by       *
+ *  the Free Software Foundation, either version 3 of the License, or          *
+ *  (at your option) any later version.                                        *
+ *                                                                             *
+ *  This program is distributed in the hope that it will be useful,            *
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of             *
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the              *
+ *  GNU General Public License for more details.                               *
+ *                                                                             *
+ *  You should have received a copy of the GNU General Public License          *
+ *  along with this program. If not, see <http://www.gnu.org/licenses/>.       *
+ *                                                                             *
+ *******************************************************************************/
+
+package com.github.shadowsocks.plugin.v2ray
+
+import android.content.ActivityNotFoundException
+import android.content.Intent
+import android.view.View
+import androidx.appcompat.app.AlertDialog
+import androidx.core.os.bundleOf
+import androidx.preference.EditTextPreferenceDialogFragmentCompat
+import com.google.android.material.snackbar.Snackbar
+
+class CertificatePreferenceDialogFragment : EditTextPreferenceDialogFragmentCompat() {
+    fun setKey(key: String) {
+        arguments = bundleOf(Pair(ARG_KEY, key))
+    }
+
+    override fun onPrepareDialogBuilder(builder: AlertDialog.Builder) {
+        super.onPrepareDialogBuilder(builder)
+        builder.setNeutralButton("Browse…") { _, _ ->
+            val activity = requireActivity()
+            try {
+                targetFragment!!.startActivityForResult(Intent(Intent.ACTION_GET_CONTENT).apply {
+                    addCategory(Intent.CATEGORY_OPENABLE)
+                    type = "application/pkix-cert"
+                }, ConfigFragment.REQUEST_BROWSE_CERTIFICATE)
+                return@setNeutralButton
+            } catch (_: ActivityNotFoundException) { } catch (_: SecurityException) { }
+            Snackbar.make(activity.findViewById<View>(R.id.content),
+                    "Please install a file manager like MiXplorer",
+                    Snackbar.LENGTH_SHORT).show()
+        }
+    }
+}
diff --git a/app/src/main/java/com/github/shadowsocks/plugin/v2ray/ConfigFragment.kt b/app/src/main/java/com/github/shadowsocks/plugin/v2ray/ConfigFragment.kt
index c7bc823..bbe2d9c 100644
--- a/app/src/main/java/com/github/shadowsocks/plugin/v2ray/ConfigFragment.kt
+++ b/app/src/main/java/com/github/shadowsocks/plugin/v2ray/ConfigFragment.kt
@@ -20,14 +20,23 @@
 
 package com.github.shadowsocks.plugin.v2ray
 
+import android.app.Activity
+import android.content.Intent
 import android.os.Bundle
+import android.view.View
 import androidx.preference.EditTextPreference
 import androidx.preference.ListPreference
 import androidx.preference.Preference
 import androidx.preference.PreferenceFragmentCompat
 import com.github.shadowsocks.plugin.PluginOptions
+import com.google.android.material.snackbar.Snackbar
+import java.lang.RuntimeException
 
 class ConfigFragment : PreferenceFragmentCompat(), Preference.OnPreferenceChangeListener {
+    companion object {
+        const val REQUEST_BROWSE_CERTIFICATE = 1
+    }
+
     private val mode by lazy { findPreference<ListPreference>("mode") }
     private val host by lazy { findPreference<EditTextPreference>("host") }
     private val path by lazy { findPreference<EditTextPreference>("path") }
@@ -53,7 +62,7 @@ class ConfigFragment : PreferenceFragmentCompat(), Preference.OnPreferenceChange
         putWithDefault("tls", tls)
         putWithDefault("host", host.text, "cloudfront.com")
         putWithDefault("path", path.text, "/")
-        putWithDefault("certRaw", certRaw.text, "")
+        putWithDefault("certRaw", certRaw.text.replace("\n", ""), "")
     }
 
     fun onInitializePluginOptions(options: PluginOptions) {
@@ -78,4 +87,29 @@ class ConfigFragment : PreferenceFragmentCompat(), Preference.OnPreferenceChange
         certRaw.isEnabled = mode != null || tls != null
         return true
     }
+
+    override fun onDisplayPreferenceDialog(preference: Preference?) {
+        if (preference == certRaw) CertificatePreferenceDialogFragment().apply {
+            setKey(certRaw.key)
+            setTargetFragment(this@ConfigFragment, 0)
+        }.show(fragmentManager ?: return, certRaw.key) else super.onDisplayPreferenceDialog(preference)
+    }
+
+    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
+        when (requestCode) {
+            REQUEST_BROWSE_CERTIFICATE -> {
+                if (resultCode != Activity.RESULT_OK) return
+                val activity = requireActivity()
+                try {
+                    // we read all its content here to avoid content URL permission issues
+                    certRaw.text = activity.contentResolver.openInputStream(data!!.data!!)!!
+                            .bufferedReader().readText()
+                } catch (e: RuntimeException) {
+                    Snackbar.make(activity.findViewById<View>(R.id.content), e.localizedMessage, Snackbar.LENGTH_LONG)
+                            .show()
+                }
+            }
+            else -> super.onActivityResult(requestCode, resultCode, data)
+        }
+    }
 }