diff --git a/400_xowa/src/gplx/xowa/apps/servers/http/Http_server_wkr.java b/400_xowa/src/gplx/xowa/apps/servers/http/Http_server_wkr.java
index 156b4e504..8bab6f667 100644
--- a/400_xowa/src/gplx/xowa/apps/servers/http/Http_server_wkr.java
+++ b/400_xowa/src/gplx/xowa/apps/servers/http/Http_server_wkr.java
@@ -136,7 +136,7 @@ public class Http_server_wkr implements Gfo_invk {
 	.Add_str_int("/exec/gfs"	, Tid_post_url_gfs)
 	;
 	private static String Convert_page(String page_html, String root_dir_http, String wiki_domain) {
-		page_html = String_.Replace(page_html, "file:////home/lnxusr/xowa/file/", "/fsys/file/");
+		page_html = Replace_fsys_hack(page_html);
 		page_html = String_.Replace(page_html, root_dir_http		, "/fsys/");
 		page_html = String_.Replace(page_html, "xowa-cmd:"			, "/exec/");
 		page_html = String_.Replace(page_html, " href=\"/wiki/"	    , " href=\"/" + wiki_domain + "/wiki/");
@@ -145,6 +145,91 @@ public class Http_server_wkr implements Gfo_invk {
 		page_html = String_.Replace(page_html, "/site"				, "");
 		return page_html;
 	}
+
+	private static final    byte[]
+	  Bry__file_lhs = Bry_.new_a7("file:")
+	, Bry__file_mid = Bry_.new_a7("/file/")
+	, Bry__file_fsys = Bry_.new_a7("/fsys")
+	;
+
+	public static String Replace_fsys_hack(String html_str) {
+		// init
+		Bry_bfr bfr = Bry_bfr_.New();
+		byte[] html_bry = Bry_.new_u8(html_str);
+		int len = html_bry.length;
+		int pos = 0;
+
+		// loop while finding "file:.*/file/"
+		while (true) {
+			// find "file:"
+			int lhs_bgn = Bry_find_.Find_fwd(html_bry, Bry__file_lhs, pos);
+
+			// exit if nothing found
+			if (lhs_bgn == Bry_find_.Not_found) 
+				break;
+
+			// set lhs_end (after "file:")
+			int lhs_end = lhs_bgn + Bry__file_lhs.length;
+
+			// skip if page literally starts with "file:"
+			if (lhs_bgn == 0) {
+				bfr.Add_mid(html_bry, pos, lhs_end);
+				pos = lhs_end;
+				continue;
+			}
+
+			// get quote char before "file:"
+			int quote_bgn = lhs_bgn - 1;
+			byte quote = html_bry[quote_bgn];
+
+			// skip if no quote found
+			if (quote != Byte_ascii.Apos && quote != Byte_ascii.Quote) {
+				bfr.Add_mid(html_bry, pos, lhs_end);
+				pos = lhs_end;
+				continue;
+			}
+
+			// find end quote
+			int quote_end = Bry_find_.Find_fwd(html_bry, quote, lhs_end);
+
+			// exit if no end quote
+			if (quote_end == Bry_find_.Not_found) 
+				break;
+
+			// skip if "'file: ... '" is too long. should be no more than 300
+			if (quote_end - lhs_end > 300) {
+				bfr.Add_mid(html_bry, pos, quote_end);
+				pos = quote_end;
+				continue;
+			}
+
+			// find "/file/"
+			int mid_bgn = Bry_find_.Find_fwd(html_bry, Bry__file_mid, lhs_bgn, quote_end);
+
+			// skip if no "/file/"
+			if (mid_bgn == Bry_find_.Not_found) {
+				bfr.Add_mid(html_bry, pos, quote_end);
+				pos = quote_end;
+				continue;
+			}
+
+			// add everything up to "file:"
+			bfr.Add_mid(html_bry, pos, lhs_bgn);
+
+			// add "/fsys/"
+			bfr.Add(Bry__file_fsys);
+
+			// add everything up to quote
+			bfr.Add_mid(html_bry, mid_bgn, quote_end);
+
+			// move pos forward
+			pos = quote_end;
+		}
+
+		// add rest
+		bfr.Add_mid(html_bry, pos, len);
+		return bfr.To_str_and_clear();
+	}
 	public Object Invk(GfsCtx ctx, int ikey, String k, GfoMsg m) {
 		if		(ctx.Match(k, Invk_run)) {this.Run();}
 		else	return Gfo_invk_.Rv_unhandled;
diff --git a/400_xowa/src/gplx/xowa/apps/servers/http/Http_server_wkr_tst.java b/400_xowa/src/gplx/xowa/apps/servers/http/Http_server_wkr_tst.java
new file mode 100644
index 000000000..c63221baf
--- /dev/null
+++ b/400_xowa/src/gplx/xowa/apps/servers/http/Http_server_wkr_tst.java
@@ -0,0 +1,51 @@
+/*
+XOWA: the XOWA Offline Wiki Application
+Copyright (C) 2012-2017 gnosygnu@gmail.com
+
+XOWA is licensed under the terms of the General Public License (GPL) Version 3,
+or alternatively under the terms of the Apache License Version 2.0.
+
+You may use XOWA according to either of these licenses as is most appropriate
+for your project on a case-by-case basis.
+
+The terms of each license can be found in the source code repository:
+
+GPLv3 License: https://github.com/gnosygnu/xowa/blob/master/LICENSE-GPLv3.txt
+Apache License: https://github.com/gnosygnu/xowa/blob/master/LICENSE-APACHE2.txt
+*/
+package gplx.xowa.apps.servers.http; import gplx.*; import gplx.xowa.*; import gplx.xowa.apps.*; import gplx.xowa.apps.servers.*;
+import org.junit.*; import gplx.core.tests.*;
+public class Http_server_wkr_tst {
+	private final    Http_server_wkr_fxt fxt = new Http_server_wkr_fxt();
+	@Test   public void File_bgn_missing() { // "file:" missing
+		fxt.Test__Replace_fsys_hack("src='file////home/lnxusr/xowa/file/'");
+	}
+	@Test   public void File_bgn_at_bos() { // "file:" at start of page
+		fxt.Test__Replace_fsys_hack("file:////home/lnxusr/xowa/file/");
+	}
+	@Test   public void Quote_bgn_missing() {
+		fxt.Test__Replace_fsys_hack("(file:////home/lnxusr/xowa/file/)");
+	}
+	@Test   public void Quote_end_missing() {
+		fxt.Test__Replace_fsys_hack("a'file:////home/lnxusr/xowa/file/");
+	}
+	@Test   public void Too_long() { // skip if too long
+		fxt.Test__Replace_fsys_hack("'file:" + String_.Repeat("a", 301) + "'");
+	}
+	@Test   public void File_mid_missing() { // skip if no /file/
+		fxt.Test__Replace_fsys_hack("'file:////home/lnxusr/xowa/file_missing/'");
+	}
+	@Test   public void One() {
+		fxt.Test__Replace_fsys_hack("'file:////home/lnxusr/xowa/file/A.png'", "'/fsys/file/A.png'");
+	}
+	@Test   public void Many() {
+		fxt.Test__Replace_fsys_hack("a 'file:////home/lnxusr/xowa/file/A.png' b \"file:////home/lnxusr/xowa/file/B.png\" c", "a '/fsys/file/A.png' b \"/fsys/file/B.png\" c");
+	}
+}
+class Http_server_wkr_fxt {
+	public void Test__Replace_fsys_hack(String html)              {Test__Replace_fsys_hack(html, html);}
+	public void Test__Replace_fsys_hack(String html, String expd) {
+		String actl = Http_server_wkr.Replace_fsys_hack(html);
+		Gftest.Eq__ary__lines(expd, actl);
+	}
+}