diff --git a/lib/private/Mail/EMailTemplate.php b/lib/private/Mail/EMailTemplate.php
index 0ba411d6926..4c56a316042 100644
--- a/lib/private/Mail/EMailTemplate.php
+++ b/lib/private/Mail/EMailTemplate.php
@@ -229,13 +229,13 @@ EOF;
 				<tr style="padding:0;text-align:left;vertical-align:top">
 					<th style="Margin:0;color:#0a0a0a;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;line-height:1.3;margin:0;padding:0;text-align:left">
 						<center data-parsed="" style="min-width:490px;width:100%%">
-							<table class="button btn default primary float-center" style="Margin:0 0 30px 0;border-collapse:collapse;border-spacing:0;display:inline-block;float:none;margin:0 0 30px 0;margin-right:15px;max-height:40px;max-width:200px;padding:0;text-align:center;vertical-align:top;width:auto">
+							<table class="button btn default primary float-center" style="Margin:0 0 30px 0;border-collapse:collapse;border-spacing:0;display:inline-block;float:none;margin:0 0 30px 0;margin-right:15px;max-height:40px;max-width:200px;padding:0;text-align:center;vertical-align:top;width:auto;background:%1\$s;background-color:%1\$s;color:#fefefe;">
 								<tr style="padding:0;text-align:left;vertical-align:top">
 									<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;border-collapse:collapse!important;color:#0a0a0a;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
 										<table style="border-collapse:collapse;border-spacing:0;padding:0;text-align:left;vertical-align:top;width:100%%">
 											<tr style="padding:0;text-align:left;vertical-align:top">
-												<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;background:%s;border:0 solid %s;border-collapse:collapse!important;color:#fefefe;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
-													<a href="%s" style="Margin:0;border:0 solid %s;border-radius:2px;color:%s;display:inline-block;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:regular;line-height:1.3;margin:0;padding:10px 25px 10px 25px;text-align:left;outline:1px solid %s;text-decoration:none">%s</a>
+												<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;border:0 solid %2\$s;border-collapse:collapse!important;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
+													<a href="%3\$s" style="Margin:0;border:0 solid %4\$s;border-radius:2px;color:%5\$s;display:inline-block;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:regular;line-height:1.3;margin:0;padding:10px 25px 10px 25px;text-align:left;outline:1px solid %6\$s;text-decoration:none">%7\$s</a>
 												</td>
 											</tr>
 										</table>
@@ -248,7 +248,7 @@ EOF;
 										<table style="border-collapse:collapse;border-spacing:0;padding:0;text-align:left;vertical-align:top;width:100%%">
 											<tr style="padding:0;text-align:left;vertical-align:top">
 												<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;background:#777;border:0 solid #777;border-collapse:collapse!important;color:#fefefe;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
-													<a href="%s" style="Margin:0;background-color:#fff;border:0 solid #777;border-radius:2px;color:#6C6C6C!important;display:inline-block;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:regular;line-height:1.3;margin:0;outline:1px solid #CBCBCB;padding:10px 25px 10px 25px;text-align:left;text-decoration:none">%s</a>
+													<a href="%8\$s" style="Margin:0;background-color:#fff;border:0 solid #777;border-radius:2px;color:#6C6C6C!important;display:inline-block;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:regular;line-height:1.3;margin:0;outline:1px solid #CBCBCB;padding:10px 25px 10px 25px;text-align:left;text-decoration:none">%9\$s</a>
 												</td>
 											</tr>
 										</table>
@@ -282,13 +282,13 @@ EOF;
 				<tr style="padding:0;text-align:left;vertical-align:top">
 					<th style="Margin:0;color:#0a0a0a;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;line-height:1.3;margin:0;padding:0;text-align:left">
 						<center data-parsed="" style="min-width:490px;width:100%%">
-							<table class="button btn default primary float-center" style="Margin:0;border-collapse:collapse;border-spacing:0;display:inline-block;float:none;margin:0;max-height:40px;padding:0;text-align:center;vertical-align:top;width:auto">
+							<table class="button btn default primary float-center" style="Margin:0;border-collapse:collapse;border-spacing:0;display:inline-block;float:none;margin:0;max-height:40px;padding:0;text-align:center;vertical-align:top;width:auto;background:%1\$s;color:#fefefe;background-color:%1\$s;">
 								<tr style="padding:0;text-align:left;vertical-align:top">
 									<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;border-collapse:collapse!important;color:#0a0a0a;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
 										<table style="border-collapse:collapse;border-spacing:0;padding:0;text-align:left;vertical-align:top;width:100%%">
 											<tr style="padding:0;text-align:left;vertical-align:top">
-												<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;background:%s;border:0 solid %s;border-collapse:collapse!important;color:#fefefe;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
-													<a href="%s" style="Margin:0;border:0 solid %s;border-radius:2px;color:%s;display:inline-block;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:regular;line-height:1.3;margin:0;padding:10px 25px 10px 25px;text-align:left;outline:1px solid %s;text-decoration:none">%s</a>
+												<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;border:0 solid %2\$;border-collapse:collapse!important;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
+													<a href="%3\$s" style="Margin:0;border:0 solid %4\$s;border-radius:2px;color:%5\$s;display:inline-block;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:regular;line-height:1.3;margin:0;padding:10px 25px 10px 25px;text-align:left;outline:1px solid %5\$s;text-decoration:none">%7\$s</a>
 												</td>
 											</tr>
 										</table>
diff --git a/tests/Settings/Mailer/NewUserMailHelperTest.php b/tests/Settings/Mailer/NewUserMailHelperTest.php
index 6d6c6bf15c6..d59b371acfd 100644
--- a/tests/Settings/Mailer/NewUserMailHelperTest.php
+++ b/tests/Settings/Mailer/NewUserMailHelperTest.php
@@ -281,12 +281,12 @@ class NewUserMailHelperTest extends TestCase {
 				<tr style="padding:0;text-align:left;vertical-align:top">
 					<th style="Margin:0;color:#0a0a0a;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;line-height:1.3;margin:0;padding:0;text-align:left">
 						<center data-parsed="" style="min-width:490px;width:100%">
-							<table class="button btn default primary float-center" style="Margin:0 0 30px 0;border-collapse:collapse;border-spacing:0;display:inline-block;float:none;margin:0 0 30px 0;margin-right:15px;max-height:40px;max-width:200px;padding:0;text-align:center;vertical-align:top;width:auto">
+							<table class="button btn default primary float-center" style="Margin:0 0 30px 0;border-collapse:collapse;border-spacing:0;display:inline-block;float:none;margin:0 0 30px 0;margin-right:15px;max-height:40px;max-width:200px;padding:0;text-align:center;vertical-align:top;width:auto;background:;background-color:;color:#fefefe;">
 								<tr style="padding:0;text-align:left;vertical-align:top">
 									<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;border-collapse:collapse!important;color:#0a0a0a;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
 										<table style="border-collapse:collapse;border-spacing:0;padding:0;text-align:left;vertical-align:top;width:100%">
 											<tr style="padding:0;text-align:left;vertical-align:top">
-												<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;background:;border:0 solid ;border-collapse:collapse!important;color:#fefefe;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
+												<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;border:0 solid ;border-collapse:collapse!important;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
 													<a href="https://example.com/resetPassword/MySuperLongSecureRandomToken" style="Margin:0;border:0 solid ;border-radius:2px;color:#ffffff;display:inline-block;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:regular;line-height:1.3;margin:0;padding:10px 25px 10px 25px;text-align:left;outline:1px solid #ffffff;text-decoration:none">Set your password</a>
 												</td>
 											</tr>
@@ -518,12 +518,12 @@ EOF;
 				<tr style="padding:0;text-align:left;vertical-align:top">
 					<th style="Margin:0;color:#0a0a0a;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;line-height:1.3;margin:0;padding:0;text-align:left">
 						<center data-parsed="" style="min-width:490px;width:100%">
-							<table class="button btn default primary float-center" style="Margin:0 0 30px 0;border-collapse:collapse;border-spacing:0;display:inline-block;float:none;margin:0 0 30px 0;margin-right:15px;max-height:40px;max-width:200px;padding:0;text-align:center;vertical-align:top;width:auto">
+							<table class="button btn default primary float-center" style="Margin:0 0 30px 0;border-collapse:collapse;border-spacing:0;display:inline-block;float:none;margin:0 0 30px 0;margin-right:15px;max-height:40px;max-width:200px;padding:0;text-align:center;vertical-align:top;width:auto;background:;background-color:;color:#fefefe;">
 								<tr style="padding:0;text-align:left;vertical-align:top">
 									<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;border-collapse:collapse!important;color:#0a0a0a;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
 										<table style="border-collapse:collapse;border-spacing:0;padding:0;text-align:left;vertical-align:top;width:100%">
 											<tr style="padding:0;text-align:left;vertical-align:top">
-												<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;background:;border:0 solid ;border-collapse:collapse!important;color:#fefefe;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
+												<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;border:0 solid ;border-collapse:collapse!important;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
 													<a href="https://example.com/" style="Margin:0;border:0 solid ;border-radius:2px;color:#ffffff;display:inline-block;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:regular;line-height:1.3;margin:0;padding:10px 25px 10px 25px;text-align:left;outline:1px solid #ffffff;text-decoration:none">Go to TestCloud</a>
 												</td>
 											</tr>
diff --git a/tests/data/emails/new-account-email-custom.html b/tests/data/emails/new-account-email-custom.html
index 601aa0b63d4..2d2e01b7ab0 100644
--- a/tests/data/emails/new-account-email-custom.html
+++ b/tests/data/emails/new-account-email-custom.html
@@ -114,12 +114,12 @@
 				<tr style="padding:0;text-align:left;vertical-align:top">
 					<th style="Margin:0;color:#0a0a0a;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;line-height:1.3;margin:0;padding:0;text-align:left">
 						<center data-parsed="" style="min-width:490px;width:100%">
-							<table class="button btn default primary float-center" style="Margin:0 0 30px 0;border-collapse:collapse;border-spacing:0;display:inline-block;float:none;margin:0 0 30px 0;margin-right:15px;max-height:40px;max-width:200px;padding:0;text-align:center;vertical-align:top;width:auto">
+							<table class="button btn default primary float-center" style="Margin:0 0 30px 0;border-collapse:collapse;border-spacing:0;display:inline-block;float:none;margin:0 0 30px 0;margin-right:15px;max-height:40px;max-width:200px;padding:0;text-align:center;vertical-align:top;width:auto;background:#0082c9;background-color:#0082c9;color:#fefefe;">
 								<tr style="padding:0;text-align:left;vertical-align:top">
 									<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;border-collapse:collapse!important;color:#0a0a0a;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
 										<table style="border-collapse:collapse;border-spacing:0;padding:0;text-align:left;vertical-align:top;width:100%">
 											<tr style="padding:0;text-align:left;vertical-align:top">
-												<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;background:#0082c9;border:0 solid #0082c9;border-collapse:collapse!important;color:#fefefe;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
+												<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;border:0 solid #0082c9;border-collapse:collapse!important;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
 													<a href="https://example.org/resetPassword/123" style="Margin:0;border:0 solid #0082c9;border-radius:2px;color:#ffffff;display:inline-block;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:regular;line-height:1.3;margin:0;padding:10px 25px 10px 25px;text-align:left;outline:1px solid #ffffff;text-decoration:none">Set your password</a>
 												</td>
 											</tr>
diff --git a/tests/data/emails/new-account-email-single-button.html b/tests/data/emails/new-account-email-single-button.html
index db8ab868682..279822e21cc 100644
--- a/tests/data/emails/new-account-email-single-button.html
+++ b/tests/data/emails/new-account-email-single-button.html
@@ -114,12 +114,12 @@
 				<tr style="padding:0;text-align:left;vertical-align:top">
 					<th style="Margin:0;color:#0a0a0a;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;line-height:1.3;margin:0;padding:0;text-align:left">
 						<center data-parsed="" style="min-width:490px;width:100%">
-							<table class="button btn default primary float-center" style="Margin:0;border-collapse:collapse;border-spacing:0;display:inline-block;float:none;margin:0;max-height:40px;padding:0;text-align:center;vertical-align:top;width:auto">
+							<table class="button btn default primary float-center" style="Margin:0;border-collapse:collapse;border-spacing:0;display:inline-block;float:none;margin:0;max-height:40px;padding:0;text-align:center;vertical-align:top;width:auto;background:#0082c9;color:#fefefe;background-color:#0082c9;">
 								<tr style="padding:0;text-align:left;vertical-align:top">
 									<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;border-collapse:collapse!important;color:#0a0a0a;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
 										<table style="border-collapse:collapse;border-spacing:0;padding:0;text-align:left;vertical-align:top;width:100%">
 											<tr style="padding:0;text-align:left;vertical-align:top">
-												<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;background:#0082c9;border:0 solid #0082c9;border-collapse:collapse!important;color:#fefefe;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
+												<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;border:0 solid border-collapse:collapse!important;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
 													<a href="https://example.org/resetPassword/123" style="Margin:0;border:0 solid #0082c9;border-radius:2px;color:#ffffff;display:inline-block;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:regular;line-height:1.3;margin:0;padding:10px 25px 10px 25px;text-align:left;outline:1px solid #ffffff;text-decoration:none">Set your password</a>
 												</td>
 											</tr>
diff --git a/tests/data/emails/new-account-email.html b/tests/data/emails/new-account-email.html
index f7ffbb8abf6..3835fc3d540 100644
--- a/tests/data/emails/new-account-email.html
+++ b/tests/data/emails/new-account-email.html
@@ -114,12 +114,12 @@
 				<tr style="padding:0;text-align:left;vertical-align:top">
 					<th style="Margin:0;color:#0a0a0a;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;line-height:1.3;margin:0;padding:0;text-align:left">
 						<center data-parsed="" style="min-width:490px;width:100%">
-							<table class="button btn default primary float-center" style="Margin:0 0 30px 0;border-collapse:collapse;border-spacing:0;display:inline-block;float:none;margin:0 0 30px 0;margin-right:15px;max-height:40px;max-width:200px;padding:0;text-align:center;vertical-align:top;width:auto">
+							<table class="button btn default primary float-center" style="Margin:0 0 30px 0;border-collapse:collapse;border-spacing:0;display:inline-block;float:none;margin:0 0 30px 0;margin-right:15px;max-height:40px;max-width:200px;padding:0;text-align:center;vertical-align:top;width:auto;background:#0082c9;background-color:#0082c9;color:#fefefe;">
 								<tr style="padding:0;text-align:left;vertical-align:top">
 									<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;border-collapse:collapse!important;color:#0a0a0a;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
 										<table style="border-collapse:collapse;border-spacing:0;padding:0;text-align:left;vertical-align:top;width:100%">
 											<tr style="padding:0;text-align:left;vertical-align:top">
-												<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;background:#0082c9;border:0 solid #0082c9;border-collapse:collapse!important;color:#fefefe;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
+												<td style="-moz-hyphens:auto;-webkit-hyphens:auto;Margin:0;border:0 solid #0082c9;border-collapse:collapse!important;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:400;hyphens:auto;line-height:1.3;margin:0;padding:0;text-align:left;vertical-align:top;word-wrap:break-word">
 													<a href="https://example.org/resetPassword/123" style="Margin:0;border:0 solid #0082c9;border-radius:2px;color:#ffffff;display:inline-block;font-family:Lucida Grande,Geneva,Verdana,sans-serif;font-size:16px;font-weight:regular;line-height:1.3;margin:0;padding:10px 25px 10px 25px;text-align:left;outline:1px solid #ffffff;text-decoration:none">Set your password</a>
 												</td>
 											</tr>