Proton Bridge vs Slack
Side-by-side trajectory, velocity, and editorial themes.
Proton's IMAP gateway is in deep maintenance, hardening fixes only.
Proton Bridge — the local IMAP/SMTP gateway that lets standard mail clients talk to Proton's encrypted backend — has settled into a hardening-and-fix rhythm. Recent releases are dominated by certificate validation fixes, mailbox conflict resolution, label/unlabel endpoint regressions, and OS compatibility work (macOS 26). No directionally new capabilities have shipped in over a year.
Cadence is steady at roughly one minor or patch release per month, structured around mistakes that bit users: a Drafts-to-Trash deletion regression in 3.23.x, the unlabel endpoint reversion in 3.24.1. The team is reacting by adding feature flags so risky logic can be toggled post-release, and by expanding Sentry instrumentation around mailbox sync and auto-update failures.
Expect more incremental protocol hardening — mailbox conflict cases, IMAP IDLE behaviour, certificate handling — gated behind feature flags. No directional product change is signaled in the changelog.
Slack rebuilds its developer platform around shipping in-channel AI agents.
Slack is well into a platform pivot, restructuring its CLI, Block Kit, and APIs around AI agent use cases. The 4.0.0 release in April formalized this with an agent-scaffolding command, sample agent apps, and a live-reloading dev workflow. Recent additions — streaming chat APIs, Card/Carousel/Alert blocks, and continued MCP server expansion — show the surface area for in-Slack agents widening fast.
The platform is shifting from 'agents can post messages' to 'agents are first-class UI citizens'. The new chat.startStream / chat.appendStream / chat.stopStream methods change what an agent reply looks like, and the Card and Carousel blocks hint at richer multi-turn agent flows. Security work on PKCE and optional scopes is keeping pace, which tells you third-party agent developers are the audience, not just first-party features.
Expect Slack to publish reference agents and likely a discovery or marketplace surface for agent apps within the next minor cycle, with streaming Block Kit becoming the canonical pattern shown in the docs.
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