docs: note the sudo case in the GitHub HTTP/2 workaround

--global writes to the config of whoever runs it, so a user updating with sudo was still prompted after applying the fix. Confirmed by a user on Raspberry Pi OS.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

README.md

@@ -16,6 +16,12 @@ A lightweight web interface providing browser-based access to MeshCore mesh netw
 > git config --global http.version HTTP/1.1
 > ```
 >
+> **Still asked for a username after that?** Then you update with `sudo`. `--global` writes to the config of the user who runs it, and root has its own — so run it for root too:
+>
+> ```bash
+> sudo git config --global http.version HTTP/1.1
+> ```
+>
 > Then update as usual. Release **2.14.0** carries the same setting inside `update.sh`, but you need the command above to reach it. Full explanation: [Update asks for a GitHub username](docs/troubleshooting.md#update-asks-for-a-github-username).
 
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docs/troubleshooting.md

@@ -194,6 +194,17 @@ Press Ctrl+C; typing a username or a token will not help.
 git config --global http.version HTTP/1.1
 ```
 
+If it still asks for a username after that, you are updating with `sudo`.
+`--global` writes to the config of the user who runs it, and root has its own —
+so set it for root as well:
+
+```bash
+sudo git config --global http.version HTTP/1.1
+```
+
+Setting it on the repository itself works too, and does not care who runs the
+update: `cd ~/mc-webui && git config http.version HTTP/1.1`.
+
 Then run `mcupdate` again. From 2.14.0 on, `update.sh` sets this for its own
 pull, so the manual command is only needed to update *to* that version — or for
 `git pull` commands you run yourself.