diff --git a/GUI.py b/GUI.py
index 2fd8900..4e0cb98 100644
--- a/GUI.py
+++ b/GUI.py
@@ -75,13 +75,13 @@ def backgrounds():
     return render_template("backgrounds.html", file="backgrounds.json")
 
 
-@app.route("/background/add", methods=["POST"])
-def background_add():
-    # Get form values
-    youtube_uri = request.form.get("youtube_uri").strip()
-    filename = request.form.get("filename").strip()
-    citation = request.form.get("citation").strip()
-    position = request.form.get("position").strip()
+@app.route("/background/add", methods=["POST"])
+def background_add():
+    # Get form values
+    youtube_uri = request.form.get("youtube_uri", "").strip()
+    filename = request.form.get("filename", "").strip()
+    citation = request.form.get("citation", "").strip()
+    position = request.form.get("position", "").strip()
 
     gui.add_background(youtube_uri, filename, citation, position)
 
diff --git a/GUI/backgrounds.html b/GUI/backgrounds.html
index ed7957e..29d68a6 100644
--- a/GUI/backgrounds.html
+++ b/GUI/backgrounds.html
@@ -108,6 +108,15 @@
     let keys = [];
     let youtube_urls = [];
 
+    function h(str) {
+        return String(str ?? '')
+            .replace(/&/g, '&')
+            .replace(/"/g, '"')
+            .replace(/'/g, ''')
+            .replace(/</g, '&lt;')
+            .replace(/>/g, '&gt;');
+    }
+
     async function loadBackgrounds() {
         try {
             const response = await fetch("backgrounds.json");
@@ -134,8 +143,8 @@
                                     allowfullscreen></iframe>
                         </div>
                         <div class="p-4">
-                            <h3 class="text-slate-200 font-medium truncate mb-1" title="${key}">${key}</h3>
-                            <p class="text-slate-500 text-xs truncate mb-4">${value[2]}</p>
+                            <h3 class="text-slate-200 font-medium truncate mb-1" title="${h(key)}">${h(key)}</h3>
+                            <p class="text-slate-500 text-xs truncate mb-4">${h(value[2])}</p>
                             
                             <div class="flex justify-end">
                                 <button onclick="confirmDelete('${key}')" class="btn btn-square btn-sm btn-ghost hover:bg-red-500/20 hover:text-red-400">
diff --git a/main.py b/main.py
index aea5b5c..2a399cf 100755
--- a/main.py
+++ b/main.py
@@ -1,5 +1,6 @@
 #!/usr/bin/env python
 import math
+import os
 import subprocess
 import sys
 from os import name
@@ -59,6 +60,12 @@ def _get_platform_post_id(config: dict, platform: str) -> str:
     return ""
 
 
+def clear_screen() -> None:
+    if name != "nt" and not os.environ.get("TERM"):
+        return
+    subprocess.run(["cls" if name == "nt" else "clear"], shell=(name == "nt"))
+
+
 def main(POST_ID=None) -> None:
     global reddit_id, reddit_object
     reddit_object = get_content_object(POST_ID)
@@ -97,7 +104,7 @@ def run_many(times) -> None:
             f'on the {x}{("th", "st", "nd", "rd", "th", "th", "th", "th", "th", "th")[x % 10]} iteration of {times}'
         )
         main()
-        subprocess.run(["cls" if name == "nt" else "clear"], shell=(name == "nt"))
+        clear_screen()
 
 
 def shutdown() -> NoReturn:
@@ -145,7 +152,7 @@ if __name__ == "__main__":
                     f'on the {index}{("st" if index % 10 == 1 else ("nd" if index % 10 == 2 else ("rd" if index % 10 == 3 else "th")))} post of {num_posts}'
                 )
                 main(post_id)
-                subprocess.run(["cls" if name == "nt" else "clear"], shell=(name == "nt"))
+                clear_screen()
         elif config["settings"]["times_to_run"]:
             run_many(config["settings"]["times_to_run"])
         else:
diff --git a/tests/test_gui_routes.py b/tests/test_gui_routes.py
new file mode 100644
index 0000000..dceadcb
--- /dev/null
+++ b/tests/test_gui_routes.py
@@ -0,0 +1,30 @@
+from unittest.mock import patch
+
+from GUI import app
+
+
+def test_background_add_handles_missing_form_fields():
+    app.testing = False
+
+    response = app.test_client().post("/background/add", data={})
+
+    assert response.status_code == 302
+    assert response.headers["Location"].endswith("/backgrounds")
+
+
+def test_background_add_passes_empty_defaults_for_missing_optional_fields():
+    app.testing = True
+
+    with patch("GUI.gui.add_background") as add_background:
+        response = app.test_client().post(
+            "/background/add",
+            data={"youtube_uri": "https://www.youtube.com/watch?v=dQw4w9WgXcQ"},
+        )
+
+    assert response.status_code == 302
+    add_background.assert_called_once_with(
+        "https://www.youtube.com/watch?v=dQw4w9WgXcQ",
+        "",
+        "",
+        "",
+    )
diff --git a/tests/test_gui_utils.py b/tests/test_gui_utils.py
index 781d9b3..19b4ed8 100644
--- a/tests/test_gui_utils.py
+++ b/tests/test_gui_utils.py
@@ -70,3 +70,32 @@ def test_add_background(mock_flash, mock_background_json, mock_template_toml):
         assert "test_new" in template_data["settings"]["background"]["background_video"]["options"]
         
         mock_flash.assert_called_with('Added "Rick-test_new.mp4" as a new background video!')
+
+
+@patch("utils.gui_utils.flash")
+def test_modify_settings_preserves_masked_secrets(mock_flash):
+    config_load = {
+        "reddit": {
+            "creds": {
+                "client_secret": "real-secret",
+                "password": "real-password",
+            }
+        }
+    }
+    checks = {
+        "reddit.creds.client_secret": {"optional": False, "type": "str"},
+        "reddit.creds.password": {"optional": False, "type": "str"},
+    }
+
+    result = gui_utils.modify_settings(
+        {
+            "reddit.creds.client_secret": "********",
+            "reddit.creds.password": "changed-password",
+        },
+        config_load,
+        checks,
+    )
+
+    assert config_load["reddit"]["creds"]["client_secret"] == "real-secret"
+    assert config_load["reddit"]["creds"]["password"] == "changed-password"
+    assert result["reddit.creds.client_secret"] == "real-secret"
diff --git a/tests/test_main.py b/tests/test_main.py
new file mode 100644
index 0000000..47448c6
--- /dev/null
+++ b/tests/test_main.py
@@ -0,0 +1,34 @@
+import os
+from unittest.mock import patch
+
+import main
+
+
+def test_clear_screen_skips_clear_without_term(monkeypatch):
+    monkeypatch.delenv("TERM", raising=False)
+    monkeypatch.setattr(main, "name", "posix")
+
+    with patch("main.subprocess.run") as run:
+        main.clear_screen()
+
+    run.assert_not_called()
+
+
+def test_clear_screen_runs_when_term_is_set(monkeypatch):
+    monkeypatch.setenv("TERM", "xterm")
+    monkeypatch.setattr(main, "name", "posix")
+
+    with patch("main.subprocess.run") as run:
+        main.clear_screen()
+
+    run.assert_called_once_with(["clear"], shell=False)
+
+
+def test_clear_screen_runs_windows_command(monkeypatch):
+    monkeypatch.delenv("TERM", raising=False)
+    monkeypatch.setattr(main, "name", "nt")
+
+    with patch("main.subprocess.run") as run:
+        main.clear_screen()
+
+    run.assert_called_once_with(["cls"], shell=True)
diff --git a/tests/test_templates.py b/tests/test_templates.py
new file mode 100644
index 0000000..37c8906
--- /dev/null
+++ b/tests/test_templates.py
@@ -0,0 +1,10 @@
+from pathlib import Path
+
+
+def test_backgrounds_template_escapes_catalog_values_before_inner_html():
+    template = Path("GUI/backgrounds.html").read_text(encoding="utf-8")
+
+    assert "function h(str)" in template
+    assert "title=\"${h(key)}\"" in template
+    assert "${h(key)}" in template
+    assert "${h(value[2])}" in template
diff --git a/utils/gui_utils.py b/utils/gui_utils.py
index 426d7c7..9fa1df8 100644
--- a/utils/gui_utils.py
+++ b/utils/gui_utils.py
@@ -7,6 +7,22 @@ import tomlkit
 from flask import flash
 
 
+MASKED_SECRET_VALUE = "********"
+SENSITIVE_SETTING_PARTS = {
+    "password",
+    "client_secret",
+    "access_token",
+    "2fa_secret",
+    "tiktok_sessionid",
+    "elevenlabs_api_key",
+    "openai_api_key",
+}
+
+
+def is_sensitive_setting(name: str) -> bool:
+    return any(part in name for part in SENSITIVE_SETTING_PARTS)
+
+
 # Get validation checks from template, keyed by dotted path
 # (e.g. "reddit.creds.username", "threads.creds.username") so that
 # leaf-key collisions across platform sections don't clobber each other.
@@ -113,6 +129,9 @@ def modify_settings(data: dict, config_load, checks: dict):
 
     # Validate and apply values
     for name, raw_value in data.items():
+        if is_sensitive_setting(name) and raw_value == MASKED_SECRET_VALUE:
+            continue
+
         value = check(raw_value, checks[name])
 
         # Value is invalid