Add SENTRY_TUNNEL option (#4298)

Co-authored-by: Tom Moor <tom.moor@gmail.com>

.env.sample

@@ -21,7 +21,7 @@ DATABASE_CONNECTION_POOL_MAX=
 
 # For redis you can either specify an ioredis compatible url like this
 REDIS_URL=redis://localhost:6379
-# or alternatively, if you would like to provide addtional connection options,
+# or alternatively, if you would like to provide additional connection options,
 # use a base64 encoded JSON connection option object. Refer to the ioredis documentation
 # for a list of available options.
 # Example: Use Redis Sentinel for high availability
@@ -38,7 +38,7 @@ PORT=3000
 COLLABORATION_URL=
 
 # To support uploading of images for avatars and document attachments an
-# s3-compatible storage must be provided. AWS S3 is recommended for redundency
+# s3-compatible storage must be provided. AWS S3 is recommended for redundancy
 # however if you want to keep all file storage local an alternative such as
 # minio (https://github.com/minio/minio) can be used.
 
@@ -131,7 +131,7 @@ ENABLE_UPDATES=true
 # available memory by 512 for a rough estimate
 WEB_CONCURRENCY=1
 
-# Override the maxium size of document imports, could be required if you have
+# Override the maximum size of document imports, could be required if you have
 # especially large Word documents with embedded imagery
 MAXIMUM_IMPORT_SIZE=5120000
 
@@ -150,8 +150,11 @@ SLACK_MESSAGE_ACTIONS=true
 # Optionally enable google analytics to track pageviews in the knowledge base
 GOOGLE_ANALYTICS_ID=
 
-# Optionally enable Sentry (sentry.io) to track errors and performance
+# Optionally enable Sentry (sentry.io) to track errors and performance,
+# and optionally add a Sentry proxy tunnel for bypassing ad blockers in the UI:
+# https://docs.sentry.io/platforms/javascript/troubleshooting/#using-the-tunnel-option)
 SENTRY_DSN=
+SENTRY_TUNNEL=
 
 # To support sending outgoing transactional emails such as "document updated" or
 # "you've been invited" you'll need to provide authentication for an SMTP server