diff --git a/lemur/plugins/lemur_acme/acme_handlers.py b/lemur/plugins/lemur_acme/acme_handlers.py
index 40de0f77..ebc2b2b4 100644
--- a/lemur/plugins/lemur_acme/acme_handlers.py
+++ b/lemur/plugins/lemur_acme/acme_handlers.py
@@ -123,9 +123,7 @@ class AcmeHandler(object):
                 current_app.config.get("IDENTRUST_CROSS_SIGNED_LE_ICA_EXPIRATION_DATE", "17/03/21"), '%d/%m/%y'):
             pem_certificate_chain = current_app.config.get("IDENTRUST_CROSS_SIGNED_LE_ICA")
         else:
-            pem_certificate_chain = orderr.fullchain_pem[
-                                    len(pem_certificate):  # noqa
-                                    ].lstrip()
+            pem_certificate_chain = orderr.fullchain_pem[len(pem_certificate):].lstrip()
 
         current_app.logger.debug(
             "{0} {1}".format(type(pem_certificate), type(pem_certificate_chain))
diff --git a/lemur/plugins/lemur_acme/challenge_types.py b/lemur/plugins/lemur_acme/challenge_types.py
index f87acc41..fd779742 100644
--- a/lemur/plugins/lemur_acme/challenge_types.py
+++ b/lemur/plugins/lemur_acme/challenge_types.py
@@ -121,9 +121,7 @@ class AcmeHttpChallenge(AcmeChallenge):
                 current_app.config.get("IDENTRUST_CROSS_SIGNED_LE_ICA_EXPIRATION_DATE", "17/03/21"), '%d/%m/%y'):
             pem_certificate_chain = current_app.config.get("IDENTRUST_CROSS_SIGNED_LE_ICA")
         else:
-            pem_certificate_chain = finalized_orderr.fullchain_pem[
-                                    len(pem_certificate):  # noqa
-                                    ].lstrip()
+            pem_certificate_chain = finalized_orderr.fullchain_pem[len(pem_certificate):].lstrip()
 
         # validation is a random string, we use it as external id, to make it possible to implement revoke_certificate
         return pem_certificate, pem_certificate_chain, None
diff --git a/lemur/plugins/lemur_acme/plugin.py b/lemur/plugins/lemur_acme/plugin.py
index 51f6aa3a..7dc7af25 100644
--- a/lemur/plugins/lemur_acme/plugin.py
+++ b/lemur/plugins/lemur_acme/plugin.py
@@ -309,7 +309,7 @@ class ACMEHttpIssuerPlugin(IssuerPlugin):
             "name": "acme_url",
             "type": "str",
             "required": True,
-            "validation": "/^http[s]?://(?:[a-zA-Z]|[0-9]|[$-_@.&+]|[!*\(\),]|(?:%[0-9a-fA-F][0-9a-fA-F]))+$/",
+            "validation": r"/^http[s]?://(?:[a-zA-Z]|[0-9]|[$-_@.&+]|[!*\(\),]|(?:%[0-9a-fA-F][0-9a-fA-F]))+$/",
             "helpMessage": "Must be a valid web url starting with http[s]://",
         },
         {
@@ -322,7 +322,7 @@ class ACMEHttpIssuerPlugin(IssuerPlugin):
             "name": "email",
             "type": "str",
             "default": "",
-            "validation": "/^?([-a-zA-Z0-9.`?{}]+@\w+\.\w+)$/",
+            "validation": r"/^?([-a-zA-Z0-9.`?{}]+@\w+\.\w+)$/",
             "helpMessage": "Email to use",
         },
         {
diff --git a/lemur/plugins/lemur_acme/tests/test_acme_handler.py b/lemur/plugins/lemur_acme/tests/test_acme_handler.py
index d9f4313d..650bf513 100644
--- a/lemur/plugins/lemur_acme/tests/test_acme_handler.py
+++ b/lemur/plugins/lemur_acme/tests/test_acme_handler.py
@@ -1,6 +1,7 @@
 import unittest
 from unittest.mock import patch, Mock
 
+from flask import Flask
 from cryptography.x509 import DNSName
 from lemur.plugins.lemur_acme import acme_handlers
 
@@ -9,6 +10,16 @@ class TestAcmeHandler(unittest.TestCase):
     def setUp(self):
         self.acme = acme_handlers.AcmeHandler()
 
+        # Creates a new Flask application for a test duration. In python 3.8, manual push of application context is
+        # needed to run tests in dev environment without getting error 'Working outside of application context'.
+        _app = Flask('lemur_test_acme')
+        self.ctx = _app.app_context()
+        assert self.ctx
+        self.ctx.push()
+
+    def tearDown(self):
+        self.ctx.pop()
+
     def test_strip_wildcard(self):
         expected = ("example.com", False)
         result = self.acme.strip_wildcard("example.com")
diff --git a/lemur/plugins/lemur_acme/tests/test_acme_http.py b/lemur/plugins/lemur_acme/tests/test_acme_http.py
index 365bcb5c..786e0eba 100644
--- a/lemur/plugins/lemur_acme/tests/test_acme_http.py
+++ b/lemur/plugins/lemur_acme/tests/test_acme_http.py
@@ -1,6 +1,7 @@
 import unittest
 from unittest.mock import patch, Mock
 
+from flask import Flask
 from acme import challenges
 from lemur.plugins.lemur_acme import plugin
 
@@ -11,6 +12,16 @@ class TestAcmeHttp(unittest.TestCase):
         self.ACMEHttpIssuerPlugin = plugin.ACMEHttpIssuerPlugin()
         self.acme = plugin.AcmeHandler()
 
+        # Creates a new Flask application for a test duration. In python 3.8, manual push of application context is
+        # needed to run tests in dev environment without getting error 'Working outside of application context'.
+        _app = Flask('lemur_test_acme')
+        self.ctx = _app.app_context()
+        assert self.ctx
+        self.ctx.push()
+
+    def tearDown(self):
+        self.ctx.pop()
+
     @patch("lemur.plugins.lemur_acme.plugin.current_app")
     def test_create_authority(self, mock_current_app):
         mock_current_app.config = Mock()