Fix #119

and space causing the screen to scroll (again)

jssrc/term_input.js

@@ -143,7 +143,7 @@ var Input = (function() {
 			if (str.length>0 && str.charCodeAt(0) >= 32) {
 //				console.log("Typed ", str);
 				// prevent space from scrolling
-				if (e.which === 32) e.preventDefault();
+				if (evt.which === 32) evt.preventDefault();
 				sendStrMsg(str);
 			}
 		});

jssrc/term_screen.js

@@ -156,7 +156,7 @@ class TermScreen {
     };
 
     this.canvas.addEventListener('mousedown', e => {
-      if (this.selection.selectable || e.altKey) {
+      if ((this.selection.selectable || e.altKey) && e.button === 0) {
         selectStart(e.offsetX, e.offsetY)
       } else {
         Input.onMouseDown(...this.screenToGrid(e.offsetX, e.offsetY),
@@ -272,8 +272,11 @@ class TermScreen {
       }
     });
     this.canvas.addEventListener('contextmenu', e => {
-      // prevent mouse keys getting stuck
-      e.preventDefault();
+      if (this.mouseMode.clicks) {
+        // prevent mouse keys getting stuck
+        e.preventDefault();
+      }
+      selectEnd(e.offsetX, e.offsetY);
     })
 
     // bind ctrl+shift+c to copy