LibreMail is an offline-first Android email client. IMAP is currently connect-per-operation (connection reuse, issue #125, is OFF by default); full-history backfill (issue #12) prefetches message bodies + attachments on unmetered networks (default FetchPolicy.WIFI_ONLY). A perf drilldown found this opens roughly 1 + K + attachments separate authenticated connections per backfill page, saturating a provider's connection/bandwidth budget and starving interactive message-opens. These tickets track making LibreMail's connection/request patterns and data usage respect each major provider's documented limits and degrade gracefully under throttling. (Outlook/Hotmail uses the Microsoft Graph REST API; Gmail, Yahoo/AOL, and iCloud use IMAP/SMTP.)
App-specific password required (standard passwords rejected over IMAP).
Optimization levers
Cap concurrent connections at 5 or fewer.
Enforce/handle the 20 MB message-size limit on send.
Connection reuse.
Depends on
Depends on / see the throttling-backoff umbrella issue #360.
## Context
LibreMail is an offline-first Android email client. IMAP is currently connect-per-operation (connection reuse, issue #125, is OFF by default); full-history backfill (issue #12) prefetches message bodies + attachments on unmetered networks (default `FetchPolicy.WIFI_ONLY`). A perf drilldown found this opens roughly `1 + K + attachments` separate authenticated connections per backfill page, saturating a provider's connection/bandwidth budget and starving interactive message-opens. These tickets track making LibreMail's connection/request patterns and data usage respect each major provider's documented limits and degrade gracefully under throttling. (Outlook/Hotmail uses the Microsoft Graph REST API; Gmail, Yahoo/AOL, and iCloud use IMAP/SMTP.)
## Documented limits
- 5-8 concurrent connections per account.
- 20 MB max message size (unless Mail Drop).
- SMTP: 1,000 messages/day, 1,000 recipients/day, 500 recipients/message.
- App-specific password required (standard passwords rejected over IMAP).
## Optimization levers
- Cap concurrent connections at 5 or fewer.
- Enforce/handle the 20 MB message-size limit on send.
- Connection reuse.
## Depends on
Depends on / see the throttling-backoff umbrella issue #360.
Blocking a user prevents them from interacting with repositories, such as opening or commenting on pull requests or issues. Learn more about blocking a user.
Context
LibreMail is an offline-first Android email client. IMAP is currently connect-per-operation (connection reuse, issue #125, is OFF by default); full-history backfill (issue #12) prefetches message bodies + attachments on unmetered networks (default
FetchPolicy.WIFI_ONLY). A perf drilldown found this opens roughly1 + K + attachmentsseparate authenticated connections per backfill page, saturating a provider's connection/bandwidth budget and starving interactive message-opens. These tickets track making LibreMail's connection/request patterns and data usage respect each major provider's documented limits and degrade gracefully under throttling. (Outlook/Hotmail uses the Microsoft Graph REST API; Gmail, Yahoo/AOL, and iCloud use IMAP/SMTP.)Documented limits
Optimization levers
Depends on
Depends on / see the throttling-backoff umbrella issue #360.