Updated healthchecks to show a link to documentation instead of trying to fix something that can often not be fixed automatically.

src/Umbraco.Core/HealthChecks/NotificationMethods/EmailNotificationMethod.cs

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+using System;
+using System.Threading.Tasks;
+using Microsoft.Extensions.Options;
+using Umbraco.Core.Configuration.Models;
+using Umbraco.Core.Mail;
+using Umbraco.Core.Models;
+using Umbraco.Core.Services;
+using Umbraco.Web;
+
+namespace Umbraco.Core.HealthChecks.NotificationMethods
+{
+    [HealthCheckNotificationMethod("email")]
+    public class EmailNotificationMethod : NotificationMethodBase
+    {
+        private readonly ILocalizedTextService _textService;
+        private readonly IRequestAccessor _requestAccessor;
+        private readonly IEmailSender _emailSender;
+        private readonly IMarkdownToHtmlConverter _markdownToHtmlConverter;
+
+        private readonly ContentSettings _contentSettings;
+
+        public EmailNotificationMethod(
+            ILocalizedTextService textService,
+            IRequestAccessor requestAccessor,
+            IEmailSender emailSender,
+            IOptions<HealthChecksSettings> healthChecksSettings,
+            IOptions<ContentSettings> contentSettings,
+            IMarkdownToHtmlConverter markdownToHtmlConverter)
+            : base(healthChecksSettings)
+        {
+            var recipientEmail = Settings?["RecipientEmail"];
+            if (string.IsNullOrWhiteSpace(recipientEmail))
+            {
+                Enabled = false;
+                return;
+            }
+
+            RecipientEmail = recipientEmail;
+
+            _textService = textService ?? throw new ArgumentNullException(nameof(textService));
+            _requestAccessor = requestAccessor;
+            _emailSender = emailSender;
+            _markdownToHtmlConverter = markdownToHtmlConverter;
+            _contentSettings = contentSettings.Value ?? throw new ArgumentNullException(nameof(contentSettings));
+        }
+
+        public string RecipientEmail { get; }
+
+        public override async Task SendAsync(HealthCheckResults results)
+        {
+            if (ShouldSend(results) == false)
+            {
+                return;
+            }
+
+            if (string.IsNullOrEmpty(RecipientEmail))
+            {
+                return;
+            }
+
+            var message = _textService.Localize("healthcheck/scheduledHealthCheckEmailBody", new[]
+            {
+                DateTime.Now.ToShortDateString(),
+                DateTime.Now.ToShortTimeString(),
+                _markdownToHtmlConverter.ToHtml(results, Verbosity)
+            });
+
+            // Include the umbraco Application URL host in the message subject so that
+            // you can identify the site that these results are for.
+            var host = _requestAccessor.GetApplicationUrl();
+
+            var subject = _textService.Localize("healthcheck/scheduledHealthCheckEmailSubject", new[] { host.ToString() });
+
+
+            var mailMessage = CreateMailMessage(subject, message);
+            await _emailSender.SendAsync(mailMessage);
+        }
+
+        private EmailMessage CreateMailMessage(string subject, string message)
+        {
+            var to = _contentSettings.Notifications.Email;
+
+            if (string.IsNullOrWhiteSpace(subject))
+                subject = "Umbraco Health Check Status";
+
+            var isBodyHtml = message.IsNullOrWhiteSpace() == false && message.Contains("<") && message.Contains("</");
+            return new EmailMessage(to, RecipientEmail, subject, message, isBodyHtml);
+        }
+    }
+}

src/Umbraco.Core/HealthChecks/NotificationMethods/IHealthCheckNotificationMethod.cs

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+using System.Threading.Tasks;
+using Umbraco.Core.Composing;
+
+namespace Umbraco.Core.HealthChecks.NotificationMethods
+{
+    public interface IHealthCheckNotificationMethod : IDiscoverable
+    {
+        bool Enabled { get; }
+
+        Task SendAsync(HealthCheckResults results);
+    }
+}

src/Umbraco.Core/HealthChecks/NotificationMethods/IMarkdownToHtmlConverter.cs

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+namespace Umbraco.Core.HealthChecks.NotificationMethods
+{
+    public interface IMarkdownToHtmlConverter
+    {
+        string ToHtml(HealthCheckResults results, HealthCheckNotificationVerbosity verbosity);
+    }
+}

src/Umbraco.Core/HealthChecks/NotificationMethods/NotificationMethodBase.cs

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+using System.Collections.Generic;
+using System.Reflection;
+using System.Threading.Tasks;
+using Microsoft.Extensions.Options;
+using Umbraco.Core.Configuration.Models;
+
+namespace Umbraco.Core.HealthChecks.NotificationMethods
+{
+    public abstract class NotificationMethodBase : IHealthCheckNotificationMethod
+    {
+        protected NotificationMethodBase(IOptions<HealthChecksSettings> healthCheckSettings)
+        {
+            var type = GetType();
+            var attribute = type.GetCustomAttribute<HealthCheckNotificationMethodAttribute>();
+            if (attribute == null)
+            {
+                Enabled = false;
+                return;
+            }
+
+            var notificationMethods = healthCheckSettings.Value.Notification.NotificationMethods;
+            if (!notificationMethods.TryGetValue(attribute.Alias, out var notificationMethod))
+            {
+                Enabled = false;
+                return;
+            }
+
+            Enabled = notificationMethod.Enabled;
+            FailureOnly = notificationMethod.FailureOnly;
+            Verbosity = notificationMethod.Verbosity;
+            Settings = notificationMethod.Settings;
+        }
+
+        public bool Enabled {  get; protected set; }
+
+        public bool FailureOnly { get; protected set; }
+
+        public HealthCheckNotificationVerbosity Verbosity { get; protected set; }
+
+        public IDictionary<string, string> Settings { get; }
+
+        protected bool ShouldSend(HealthCheckResults results)
+        {
+            return Enabled && (!FailureOnly || !results.AllChecksSuccessful);
+        }
+
+        public abstract Task SendAsync(HealthCheckResults results);
+    }
+}