diff --git a/.gitea/workflows/flatpak.yml b/.gitea/workflows/flatpak.yml
index d25879c6..3605b585 100644
--- a/.gitea/workflows/flatpak.yml
+++ b/.gitea/workflows/flatpak.yml
@@ -73,8 +73,34 @@ jobs:
       # sufficient — the Tooling step's dnf install pulls a systemd package upgrade whose RPM
       # trigger re-runs authselect and regenerates this file, undoing the fix. It's reapplied
       # there, right before the first `flatpak` network call.
-      - name: Fix container DNS (drop nss-resolve — no systemd-resolved in CI)
-        run: sed -i 's/resolve \[!UNAVAIL=return\] //' /etc/nsswitch.conf
+      - name: Fix container DNS (drop nss-resolve, resolve over TCP)
+        run: |
+          sed -i 's/resolve \[!UNAVAIL=return\] //' /etc/nsswitch.conf
+          # Resolve over TCP instead of UDP. The documented root cause of the flathub
+          # bootstrap failures (investigated 2026-07-11, see the Tooling step) is this box's
+          # Docker embedded resolver at 127.0.0.11 DROPPING UDP lookups while the shared
+          # runner fleet is saturated — a datagram nobody retransmits, so the lookup just
+          # times out. The answer then was to widen retry.sh's budget to 10 attempts (~9 min),
+          # which is enough to outlast a main push's ~8-workflow fan-out but NOT a TAG push's
+          # 13: v0.15.0 (twice) and v0.16.0 each burned all 10 attempts and failed the job,
+          # each needing a manual re-run.
+          #
+          # `use-vc` makes glibc use TCP, where the kernel retransmits and the query cannot be
+          # silently lost under load. Same resolver, same search path — only the transport
+          # changes, so internal names (git.unom.io) resolve exactly as before; deliberately
+          # NO extra nameservers, which would risk answering an internal name from a public
+          # resolver. Docker's embedded DNS serves TCP on 127.0.0.11:53 as well as UDP.
+          # retry.sh stays as the backstop for genuine upstream blips.
+          #
+          # Non-fatal: Docker bind-mounts /etc/resolv.conf and can present it read-only, and a
+          # DNS tuning that cannot be applied must not be what fails the release build — that
+          # would trade an occasional re-run for a hard stop. Falling back to UDP just restores
+          # today's behaviour, which retry.sh already covers.
+          if ! grep -q '^options .*use-vc' /etc/resolv.conf 2>/dev/null; then
+            echo 'options use-vc timeout:3 attempts:3' >> /etc/resolv.conf \
+              || echo "::warning::could not set use-vc (read-only resolv.conf?); staying on UDP"
+          fi
+          cat /etc/resolv.conf || true
 
       # fedora:43 has no node, but actions/checkout (a JS action) needs it. A plain `run:` step
       # executes via the container shell (no node needed), so install node BEFORE checkout.