diff --git a/copyparty/web/baguettebox.js b/copyparty/web/baguettebox.js
index 5596eb6e..4b132a49 100644
--- a/copyparty/web/baguettebox.js
+++ b/copyparty/web/baguettebox.js
@@ -1,3 +1,5 @@
+"use strict";
+
 /*!
  * baguetteBox.js
  * @author  feimosi
@@ -5,6 +7,8 @@
  * @url https://github.com/feimosi/baguetteBox.js
  */
 
+var J_BBX = 1;
+
 window.baguetteBox = (function () {
     'use strict';
 
@@ -1359,3 +1363,5 @@ window.baguetteBox = (function () {
         destroy: destroyPlugin
     };
 })();
+
+J_BBX = 2;
diff --git a/copyparty/web/browser.html b/copyparty/web/browser.html
index 0fcbadf3..e8a91c5a 100644
--- a/copyparty/web/browser.html
+++ b/copyparty/web/browser.html
@@ -156,7 +156,13 @@
 	{%- if js %}
 	<script src="{{ js }}_={{ ts }}"></script>
 	{%- endif %}
+	<script>
+		Date.now();function jsldp(a,b){2!=window[a]&&alert("FATAL ERROR: cannot load "+b+".js due to unreliable network or broken reverse-proxy; try CTRL-SHIFT-R")}
+		jsldp("J_UTL","util");
+		jsldp("J_BBX","baguettebox");
+		jsldp("J_BRW","browser");
+		jsldp("J_U2K","up2k");
+	</script>
 </body>
-
 </html>
 
diff --git a/copyparty/web/browser.js b/copyparty/web/browser.js
index 1f281b25..2e645fbd 100644
--- a/copyparty/web/browser.js
+++ b/copyparty/web/browser.js
@@ -1,5 +1,7 @@
 "use strict";
 
+var J_BRW = 1;
+
 var XHR = XMLHttpRequest,
 	img_re = /\.(a?png|avif|bmp|gif|heif|jpe?g|jfif|svg|webp|webm|mkv|mp4|m4v|mov)(\?|$)/i;
 
@@ -9710,3 +9712,5 @@ function reload_browser() {
 	msel.render();
 }
 treectl.hydrate();
+
+J_BRW = 2;
diff --git a/copyparty/web/idp.html b/copyparty/web/idp.html
index f6e71d63..9db4b88c 100644
--- a/copyparty/web/idp.html
+++ b/copyparty/web/idp.html
@@ -50,6 +50,10 @@ document.documentElement.className = (STG && STG.cpp_thm) || "{{ this.args.theme
 {%- if js %}
 <script src="{{ js }}_={{ ts }}"></script>
 {%- endif %}
+<script>
+    Date.now();function jsldp(a,b){2!=window[a]&&alert("FATAL ERROR: cannot load "+b+".js due to unreliable network or broken reverse-proxy; try CTRL-SHIFT-R")}
+    jsldp("J_UTL","util");
+</script>
 </body>
 </html>
 
diff --git a/copyparty/web/md.html b/copyparty/web/md.html
index f2148a91..d1a186ec 100644
--- a/copyparty/web/md.html
+++ b/copyparty/web/md.html
@@ -161,8 +161,17 @@ try { l.light = drk? 0:1; } catch (ex) { }
 	{%- if edit %}
 	<script src="{{ r }}/.cpr/md2.js?_={{ ts }}"></script>
 	{%- endif %}
+	<script>
+		Date.now();function jsldp(a,b){2!=window[a]&&alert("FATAL ERROR: cannot load "+b+".js due to unreliable network or broken reverse-proxy; try CTRL-SHIFT-R")}
+		jsldp("J_UTL","util");
+		jsldp("J_MD","md");
+		{%- if edit %}
+		jsldp("J_MD2","md2");
+		{%- endif %}
+	</script>
 	{%- if js %}
 	<script src="{{ js }}_={{ ts }}"></script>
 	{%- endif %}
-</body></html>
+</body>
+</html>
 
diff --git a/copyparty/web/md.js b/copyparty/web/md.js
index 7889f4f3..9ecfca4b 100644
--- a/copyparty/web/md.js
+++ b/copyparty/web/md.js
@@ -1,5 +1,6 @@
 "use strict";
 
+var J_MD = 1;
 var dom_toc = ebi('toc'),
     dom_wrap = ebi('mw'),
     dom_hbar = ebi('mh'),
@@ -524,3 +525,5 @@ if (sread('hidenav') == 1)
 
 if (window.tt && tt.init)
     tt.init();
+
+J_MD = 2;
diff --git a/copyparty/web/md2.js b/copyparty/web/md2.js
index 29243107..0582b6e1 100644
--- a/copyparty/web/md2.js
+++ b/copyparty/web/md2.js
@@ -1,6 +1,7 @@
 "use strict";
 
 
+var J_MD2 = 1;
 var sloc0 = '' + location,
     dbg_kbd = /[?&]dbgkbd\b/.exec(sloc0);
 
@@ -1230,3 +1231,5 @@ action_stack = (function () {
         _ref: ref
     }
 })();
+
+J_MD2 = 2;
diff --git a/copyparty/web/mde.html b/copyparty/web/mde.html
index f6d0940f..47bf8d0c 100644
--- a/copyparty/web/mde.html
+++ b/copyparty/web/mde.html
@@ -57,5 +57,10 @@ try { l.light = drk? 0:1; } catch (ex) { }
 	{%- if js %}
 	<script src="{{ js }}_={{ ts }}"></script>
 	{%- endif %}
+	<script>
+		Date.now();function jsldp(a,b){2!=window[a]&&alert("FATAL ERROR: cannot load "+b+".js due to unreliable network or broken reverse-proxy; try CTRL-SHIFT-R")}
+		jsldp("J_UTL","util");
+		jsldp("J_MDE","mde");
+	</script>
 </body></html>
 
diff --git a/copyparty/web/mde.js b/copyparty/web/mde.js
index 058825c9..e44c9803 100644
--- a/copyparty/web/mde.js
+++ b/copyparty/web/mde.js
@@ -1,5 +1,6 @@
 "use strict";
 
+var J_MDE = 1;
 var dom_wrap = ebi('mw');
 var dom_nav = ebi('mn');
 var dom_doc = ebi('m');
@@ -199,3 +200,5 @@ function save_chk() {
 
     toast.ok(2, 'save OK' + (this.ntry ? '\nattempt ' + this.ntry : ''));
 }
+
+J_MDE = 2;
diff --git a/copyparty/web/rups.html b/copyparty/web/rups.html
index 2cc0443a..544c1ac1 100644
--- a/copyparty/web/rups.html
+++ b/copyparty/web/rups.html
@@ -39,6 +39,11 @@ document.documentElement.className = (STG && STG.cpp_thm) || "{{ this.args.theme
 {%- if js %}
 <script src="{{ js }}_={{ ts }}"></script>
 {%- endif %}
+<script>
+	Date.now();function jsldp(a,b){2!=window[a]&&alert("FATAL ERROR: cannot load "+b+".js due to unreliable network or broken reverse-proxy; try CTRL-SHIFT-R")}
+	jsldp("J_UTL","util");
+	jsldp("J_RUP","rups");
+</script>
 </body>
 </html>
 
diff --git a/copyparty/web/rups.js b/copyparty/web/rups.js
index e4e8b3ce..3aa80be2 100644
--- a/copyparty/web/rups.js
+++ b/copyparty/web/rups.js
@@ -1,3 +1,7 @@
+"use strict";
+
+var J_RUP = 1;
+
 function render() {
     var html = ['<table id="tab"><thead><tr><th>size</th><th>who</th><th>ip</th><th>when</th><th>age</th><th>dir</th><th>file</th></tr></thead><tbody>'];
     var ups = V.ups, now = V.now;
@@ -67,3 +71,5 @@ ebi('filter').onkeydown = function (e) {
     if (('' + e.key).endsWith('Enter'))
         ask();
 };
+
+J_RUP = 2;
diff --git a/copyparty/web/shares.html b/copyparty/web/shares.html
index c85a641d..fcb53cad 100644
--- a/copyparty/web/shares.html
+++ b/copyparty/web/shares.html
@@ -79,6 +79,11 @@ document.documentElement.className = (STG && STG.cpp_thm) || "{{ this.args.theme
 {%- if js %}
 <script src="{{ js }}_={{ ts }}"></script>
 {%- endif %}
+<script>
+    Date.now();function jsldp(a,b){2!=window[a]&&alert("FATAL ERROR: cannot load "+b+".js due to unreliable network or broken reverse-proxy; try CTRL-SHIFT-R")}
+    jsldp("J_UTL","util");
+    jsldp("J_SHR","shares");
+</script>
 </body>
 </html>
 
diff --git a/copyparty/web/shares.js b/copyparty/web/shares.js
index d03f8086..3e627446 100644
--- a/copyparty/web/shares.js
+++ b/copyparty/web/shares.js
@@ -1,3 +1,7 @@
+"use strict";
+
+var J_SHR = 1;
+
 var t = QSA('a[k]');
 for (var a = 0; a < t.length; a++)
     t[a].onclick = rm;
@@ -81,3 +85,5 @@ function showqr(href) {
     for (var a = 0; a < aa; a++)
         btns[a].onclick = bump;
 })();
+
+J_SHR = 2;
diff --git a/copyparty/web/splash.html b/copyparty/web/splash.html
index b57ff3f7..4f95eff1 100644
--- a/copyparty/web/splash.html
+++ b/copyparty/web/splash.html
@@ -224,6 +224,11 @@ document.documentElement.className = (STG && STG.cpp_thm) || "{{ this.args.theme
 {%- if js %}
 <script src="{{ js }}_={{ ts }}"></script>
 {%- endif %}
+<script>
+	Date.now();function jsldp(a,b){2!=window[a]&&alert("FATAL ERROR: cannot load "+b+".js due to unreliable network or broken reverse-proxy; try CTRL-SHIFT-R")}
+	jsldp("J_UTL","util");
+	jsldp("J_SPL","splash");
+</script>
 </body>
 </html>
 
diff --git a/copyparty/web/splash.js b/copyparty/web/splash.js
index 4a70d0f4..6d8e635b 100644
--- a/copyparty/web/splash.js
+++ b/copyparty/web/splash.js
@@ -1,3 +1,7 @@
+"use strict";
+
+var J_SPL = 1;
+
 Ls.eng = {
 	"splash": {
 		"d2": "shows the state of all active threads",
@@ -121,3 +125,5 @@ if (ebi('lp'))
 		ebi('lm').innerHTML = this.value.length <= 64 ?
 			'' : 'ERROR: Password too long (max=64)';
 	};
+
+J_SPL = 2;
diff --git a/copyparty/web/svcs.html b/copyparty/web/svcs.html
index a0bed2c7..98348981 100644
--- a/copyparty/web/svcs.html
+++ b/copyparty/web/svcs.html
@@ -362,6 +362,11 @@ document.documentElement.className = (STG && STG.cpp_thm) || "{{ args.theme }}";
 {%- if js %}
 <script src="{{ js }}_={{ ts }}"></script>
 {%- endif %}
+<script>
+	Date.now();function jsldp(a,b){2!=window[a]&&alert("FATAL ERROR: cannot load "+b+".js due to unreliable network or broken reverse-proxy; try CTRL-SHIFT-R")}
+	jsldp("J_UTL","util");
+	jsldp("J_SVC","svcs");
+</script>
 </body>
 </html>
 
diff --git a/copyparty/web/svcs.js b/copyparty/web/svcs.js
index 0b0f6b91..e34ed949 100644
--- a/copyparty/web/svcs.js
+++ b/copyparty/web/svcs.js
@@ -1,3 +1,7 @@
+"use strict";
+
+var J_SVC = 1;
+
 var oa = QSA('pre');
 for (var a = 0; a < oa.length; a++) {
     var html = oa[a].innerHTML,
@@ -104,3 +108,5 @@ ebi('qr').onclick = function () {
     var txt = esc(url) + '<img class="b64" width="100" height="100" src="' + addq(url, 'qr') + '" />';
     modal.alert(txt);
 };
+
+J_SVC = 2;
diff --git a/copyparty/web/up2k.js b/copyparty/web/up2k.js
index 418ff31b..1a9f3d67 100644
--- a/copyparty/web/up2k.js
+++ b/copyparty/web/up2k.js
@@ -1,5 +1,6 @@
 "use strict";
 
+var J_U2K = 1;
 
 (function () {
     var x = sread('nosubtle');
@@ -3464,3 +3465,5 @@ if (ls0)
         }
         catch (ex) { }
 })();
+
+J_U2K = 2;
diff --git a/copyparty/web/util.js b/copyparty/web/util.js
index ba9c159f..226d2358 100644
--- a/copyparty/web/util.js
+++ b/copyparty/web/util.js
@@ -1,5 +1,7 @@
 "use strict";
 
+var J_UTL = 1;
+
 if (!window.console || !console.log)
     window.console = {
         "log": function (msg) { }
@@ -2349,3 +2351,5 @@ function xhrchk(xhr, prefix, e404, lvl, tag) {
 
     return fun(0, prefix + xhr.status + ": " + errtxt, tag);
 }
+
+J_UTL = 2;