diff --git a/README.md b/README.md
index c338dce..bb52ecd 100644
--- a/README.md
+++ b/README.md
@@ -43,24 +43,24 @@ The *default* profile is used whenever the plugin cannot match the Twingle
project ID from any other profile. Therefore the default profile will be used
for all newly created Twingle projects.
-| Label | Description |
-|---------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
-| Profile name | Internal name, used inside the extension. |
-| Project IDs | Twingle project IDs. Separate multiple IDs with commas. |
-| Location type | Specify how the address data sent by the form should be categorised in CiviCRM. The list is based on your CiviCRM configuration. |
-| Location type for organisations | Specify how the address data sent by the form should be categorised in CiviCRM for organisational donations. The list is based on your CiviCRM configuration. |
-| Financial type | Specify which financial type incoming one-time donations should be recorded with in CiviCRM. The list is based on your CiviCRM configuration. |
-| Financial type (recurring) | Specify which financial type incoming recurring donations should be recorded with in CiviCRM. The list is based on your CiviCRM configuration. |
-| CiviSEPA creditor | When enabled to integrate with CiviSEPA, specify the CiviSEPA creditor to use. |
-| Gender options | Specify which CiviCRM gender option the incoming Twingle gender value should be mapped to. The list is based on your CiviCRM configuration. |
-| Record *Payment method* as | Specifiy the payment methods mapping for incoming donations for each Twingle payment method. |
-| Double Opt-In | Let CiviCRM handle the double opt-in. Group memberships for newsletter mailing lists stay pending until the subscription gets confirmed. Note that this only works for public mailing lists. Any non-public mailing lists will be ignored. Do not forget to disable Twingle's double opt-in option in the Twingle Manager. |
-| Sign up for groups | Whenever the donor checked the newsletter/postal mailing/donation receipt checkbox on the Twingle form, the contact will be added to the groups listed here. |
-| Assign donation to campaign | The donation will be assigned to the selected campaign. If a campaign ID is being submitted using the `campaign_id` parameter, this setting will be overridden with the submitted value. |
-| Create membership of type | A membership of the selected type will be created for the Individual contact for incoming one-time donations. If no membership type is selected, no membership will be created. |
-| Create membership of type (recurring) | A membership of the selected type will be created for the Individual contact for incoming recurring donations. If no membership type is selected, no membership will be created. |
-| Contribution source | The configured value will be set as the "Source" field for the contribution. |
-| Custom field mapping | Additional field values may be set to CiviCRM custom fields using a mapping. See the option's help text for the exact format. |
+| Label | Description |
+|---------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| Profile name | Internal name, used inside the extension. |
+| Project IDs | Twingle project IDs. Separate multiple IDs with commas. |
+| Location type | Specify how the address data sent by the form should be categorised in CiviCRM. The list is based on your CiviCRM configuration. |
+| Location type for organisations | Specify how the address data sent by the form should be categorised in CiviCRM for organisational donations. The list is based on your CiviCRM configuration. |
+| Financial type | Specify which financial type incoming one-time donations should be recorded with in CiviCRM. The list is based on your CiviCRM configuration. |
+| Financial type (recurring) | Specify which financial type incoming recurring donations should be recorded with in CiviCRM. The list is based on your CiviCRM configuration. |
+| CiviSEPA creditor | When enabled to integrate with CiviSEPA, specify the CiviSEPA creditor to use. |
+| Gender options | Specify which CiviCRM gender option the incoming Twingle gender value should be mapped to. The list is based on your CiviCRM configuration. |
+| Record *Payment method* as | Specifiy the payment methods mapping for incoming donations for each Twingle payment method. |
+| Double Opt-In | Let CiviCRM handle the double opt-in. Group memberships for newsletter mailing lists stay pending until the subscription gets confirmed. Note that this only works for public mailing lists. Any non-public mailing list will be ignored. Do not forget to disable Twingle's double opt-in option in the Twingle Manager. |
+| Sign up for groups | Whenever the donor checked the newsletter/postal mailing/donation receipt checkbox on the Twingle form, the contact will be added to the groups listed here. |
+| Assign donation to campaign | The donation will be assigned to the selected campaign. If a campaign ID is being submitted using the `campaign_id` parameter, this setting will be overridden with the submitted value. |
+| Create membership of type | A membership of the selected type will be created for the Individual contact for incoming one-time donations. If no membership type is selected, no membership will be created. |
+| Create membership of type (recurring) | A membership of the selected type will be created for the Individual contact for incoming recurring donations. If no membership type is selected, no membership will be created. |
+| Contribution source | The configured value will be set as the "Source" field for the contribution. |
+| Custom field mapping | Additional field values may be set to CiviCRM custom fields using a mapping. See the option's help text for the exact format. |
## API documentation
diff --git a/templates/CRM/Twingle/Form/Profile.hlp b/templates/CRM/Twingle/Form/Profile.hlp
index 12136cb..bcbe78a 100644
--- a/templates/CRM/Twingle/Form/Profile.hlp
+++ b/templates/CRM/Twingle/Form/Profile.hlp
@@ -39,7 +39,8 @@
{/htxt}
{htxt id='id-newsletter-double-opt-in'}
- {ts domain="de.systopia.twingle"}Select whether to use CiviCRM's Double-Opt-In feature for subscribing to mailing lists. Note that this only works for public mailing lists. Any non-public mailing list selected above will be ignored when this setting is enabled.{/ts}
+ {ts domain="de.systopia.twingle"}Select whether to use CiviCRM's Double-Opt-In feature for subscribing to mailing lists. Note that this only works for public mailing lists. Any non-public mailing list selected above will be ignored when this setting is enabled.{/ts}
+ {ts domain="de.systopia.twingle"}Also, do not forget to disable Twingle's own Double Opt-In option in the Twingle Manager to avoid subscribers receiving multiple confirmation e-mails. Only one or the other option should be enabled.{/ts}
{/htxt}
{htxt id='id-membership-postprocessing-call'}