setupWiFiManager() disables the config portal whenever /config.json exists
(a security measure to avoid exposing the config data + OTA page). But if the
saved WiFi credentials are lost while config.json remains -- e.g. the NVS
partition is erased ({"cmd":"erase"}, or corruption) -- the gateway can no
longer connect AND the portal is suppressed: autoConnect() fails immediately
and the failure path calls ESPRestart(3). The device then reboot-loops
forever, un-onboardable, its SoftAP flickering up ~1s per cycle.
Only suppress the portal when config.json exists AND saved STA credentials
are still present (WiFi.SSID() non-empty). With no credentials the portal
stays enabled, so the gateway raises a stable onboarding AP and can be
re-provisioned instead of reboot-looping. The original security intent is
preserved for provisioned gateways (which always have saved credentials).
Reproduced + verified on a Theengs Plug (esp32dev, min_spiffs): with NVS
erased and config.json present, the SoftAP is now stable and accepts
provisioning via the captive portal, rejoining the broker normally.
Claude-Session: https://claude.ai/code/session_01MbmZRv67fnNvzpyvqPi6vx
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
