diff --git a/src/main.c b/src/main.c
index 005da84..08d3eb2 100644
--- a/src/main.c
+++ b/src/main.c
@@ -85,7 +85,8 @@ static void update_fkeys(void)
         }
     }
     else if(app.fkmenu == FK_EDITOR_SOURCE) {
-        fkeys_sprintf(app.fkeys, "@SAVE;%s;;;;",
+        fkeys_sprintf(app.fkeys, "%s;%s;;;;",
+            !app.source->no_origin ? "@SAVE" : "",
             app.source->intf->cap & SOURCE_SAVEAS ? "@SAVE AS" : "");
     }
     else if(app.fkmenu == FK_EDITOR_OPEN) {
@@ -239,6 +240,19 @@ static void render_stats_histogram(int x, int y)
     }
 }
 
+static void open_source(source_t *source, bool insert)
+{
+    app.source = source;
+    app.fkmenu = FK_EDITOR;
+    app.insert = insert;
+    if(app.source)
+        source_load(app.source, 0, 2048);
+    heditor_set_source(app.editor, app.source);
+    heditor_set_insert_mode(app.editor, app.insert);
+    update_fkeys();
+    update_status();
+}
+
 void hex_view(void)
 {
     memset(&app, 0, sizeof app);
@@ -378,25 +392,20 @@ void hex_view(void)
                 if(browser_mode == OPEN_LF || browser_mode == OPEN_LZ) {
                     if(app.source)
                         source_free(app.source);
-                    app.source = (browser_mode == OPEN_LZ)
+                    open_source(browser_mode == OPEN_LZ
                         ? source_lazy_file_open(file)
-                        : source_loaded_file_open(file);
-                    app.fkmenu = FK_EDITOR;
-                    app.insert = false;
-                    source_load(app.source, 0, 2048);
-                    heditor_set_source(mem, app.source);
-                    heditor_set_insert_mode(mem, app.insert);
-                    update_fkeys();
+                        : source_loaded_file_open(file), false);
+                    jscene_show_and_focus(scene, mem);
                 }
                 else if(browser_mode == SAVE_AS) {
                     if(heditor_save(mem, file)) {
                         app.fkmenu = FK_EDITOR;
                         update_fkeys();
                     }
+                    jscene_show_and_focus(scene, mem);
+                    update_status();
                 }
             }
-            jscene_show_and_focus(scene, mem);
-            update_status();
         }
         if(e.type == HEDITOR_CHANGED) {
             update_status();
@@ -448,7 +457,7 @@ void hex_view(void)
             }
         }
         else if(app.fkmenu == FK_EDITOR_SOURCE) {
-            if(key == KEY_F1 && app.source) {
+            if(key == KEY_F1 && app.source && !app.source->no_origin) {
                 if(heditor_save(mem, NULL)) {
                     app.fkmenu = FK_EDITOR;
                     update_fkeys();
@@ -490,7 +499,12 @@ void hex_view(void)
                 /* TODO: Memory browser */
             }
             else if(key == KEY_F4) {
-                /* TODO: New empty source */
+                if(!has_unsaved_changes() || confirm_discard()) {
+                    if(app.source)
+                        source_free(app.source);
+                    open_source(source_loaded_file_new(), true);
+                    jscene_show_and_focus(scene, mem);
+                }
             }
             else if(key == KEY_EXIT) {
                 app.fkmenu = FK_EDITOR;
diff --git a/src/source-loaded-file.c b/src/source-loaded-file.c
index 15ad317..4362cec 100644
--- a/src/source-loaded-file.c
+++ b/src/source-loaded-file.c
@@ -136,3 +136,28 @@ fail:
     lf_free(lf);
     return NULL;
 }
+
+source_t *source_loaded_file_new(void)
+{
+    source_t *source = NULL;
+    loaded_file_t *lf = NULL;
+
+    lf = calloc(1, sizeof *lf);
+    if(!lf) goto fail;
+
+    lf->original_size = 0;
+    lf->buf = buffer_create(4096, 4096);
+    if(!lf->buf) goto fail;
+    lf->buf->data_size = 0;
+
+    source = source_open(&lf_intf, lf, "<New file>");
+    if(!source) goto fail;
+
+    source->no_origin = true;
+    return source;
+
+fail:
+    free(source);
+    lf_free(lf);
+    return NULL;
+}
diff --git a/src/source-loaded-file.h b/src/source-loaded-file.h
index e39854c..c2ac813 100644
--- a/src/source-loaded-file.h
+++ b/src/source-loaded-file.h
@@ -23,3 +23,5 @@ typedef struct {
 } loaded_file_t;
 
 source_t *source_loaded_file_open(char const *path);
+
+source_t *source_loaded_file_new(void);
diff --git a/src/source.c b/src/source.c
index ea50855..f79fee6 100644
--- a/src/source.c
+++ b/src/source.c
@@ -9,6 +9,7 @@ source_t *source_open(source_intf_t *intf, void *cookie, char const *origin)
     if(!s) goto fail;
 
     s->origin = strdup(origin);
+    s->no_origin = false;
     if(!s->origin) goto fail;
 
     s->buf = buffer_create(0, 1024);
diff --git a/src/source.h b/src/source.h
index 6c9912e..8f46464 100644
--- a/src/source.h
+++ b/src/source.h
@@ -53,8 +53,11 @@ typedef struct {
     /* Interface identifier, and opaque interface data */
     source_intf_t *intf;
     void *cookie;
-    /* Source name. Can be any string: file path, "memory at X", etc */
+    /* Source name. Can be any string: file path, "memory at X", etc. */
     char *origin;
+    /* If set, there is no origin and the "SAVE" button is disabled (only
+       useful if "SAVE AS" is enabled) */
+    bool no_origin;
     /* Front buffer for edition */
     buffer_t *buf;
     /* Address of the front buffer in the source */