update: Note that blocking cookies on Thunderbird may affect email logins (#2741)

Signed-off-by: Jonah Aragon <jonah@privacyguides.org>
Signed-off-by: Freddy <freddy@privacyguides.org>
Signed-off-by: Daniel Gray <dngray@privacyguides.org>

docs/email-clients.md

@@ -51,6 +51,8 @@ OpenPGP also does not support [forward secrecy](https://en.wikipedia.org/wiki/Fo
 
 #### Recommended Configuration
 
+<div class="annotate" markdown>
+
 We recommend changing some of these settings to make Thunderbird a little more private.
 
 These options can be found in :material-menu: → **Settings** → **Privacy & Security**.
@@ -58,7 +60,11 @@ These options can be found in :material-menu: → **Settings** → **Privacy & S
 ##### Web Content
 
 - [ ] Uncheck  **Remember websites and links I've visited**
-- [ ] Uncheck  **Accept cookies from sites**
+- [ ] Uncheck  **Accept cookies from sites** (1)
+
+</div>
+
+1. You may need to keep this setting checked when you're logging in to some providers such as Gmail, or via an institution’s SSO. You should uncheck it once you log in successfully.
 
 ##### Telemetry