docs(en): write configuration pages

docs/en-US/configuration/logging.md

@@ -1 +1,28 @@
 # Logging
+
+termscp writes a log file for each session, located at:
+
+- `$HOME/.cache/termscp/termscp.log` on Linux/BSD
+- `$HOME/Library/Caches/termscp/termscp.log` on macOS
+- `FOLDERID_LocalAppData\termscp\termscp.log` on Windows
+
+The log is not rotated: it is truncated on each launch of termscp. If you want
+to report an issue and attach the log file, save the log somewhere safe before
+launching termscp again.
+
+By default the log reports at the `INFO` level, so it is not very verbose.
+
+## Reproducing an issue at TRACE level
+
+To submit an issue, reproduce the problem with the log level set to `TRACE` by
+launching termscp with the `-D` CLI option.
+
+## Disabling logging
+
+To turn logging off, start termscp with the `-q` or `--quiet` option. You can
+alias termscp to make it persistent.
+
+## Security
+
+The log file does not contain any plaintext password. It exposes the same
+information as the sibling `bookmarks` file.