diff --git a/readme.md b/readme.md
index d1538f1..d0aa93c 100644
--- a/readme.md
+++ b/readme.md
@@ -40,7 +40,7 @@ if (src.match(/^(file|https)?:\/\/|^\/\//)) {
 
 ## bugs
 
-* output seems to be offset by 1 tile? check whether iteration is from 0-15 or from 1-16
+* output seems to be offset by 1 tile? check whether iteration is from 0-15 or from 1-16 (update: seems to go from 0-15 initially, then 0-16?)
 
 ## to do
 
@@ -53,6 +53,7 @@ if (src.match(/^(file|https)?:\/\/|^\/\//)) {
 * reorganise the page layout for a more logical workflow
 * handle animated tiles?
 * profile script performance and optimise where most needed
+* make brightness slider trigger redraw every so often while being dragged, instead of waiting until drag stop
 
 ## could do