diff --git a/src/signs_gui.cpp b/src/signs_gui.cpp
--- a/src/signs_gui.cpp
+++ b/src/signs_gui.cpp
@@ -95,6 +95,8 @@
 
 		this->vscroll.cap = this->nested_array[SLW_LIST]->current_y / this->resize.step_height;
 		this->resize.height -= this->height % this->resize.step_height; // minimum height
+>>>> Don't touch this height variable, the nested widget system takes care of it. For minimal size setting, use UpdateWidgetSize().
+>>>> Most likely some or all of these variables will become obsolete.
 
 		/* Create initial list */
 		this->signs.ForceRebuild();
@@ -113,6 +115,8 @@
 	{
 		switch (widget) {
 			case SLW_LIST: { // The list has to be drawn
+>>>> Comment has little added value, it seems.
+
 				/* No signs? */
 				uint y = r.top + 2; // Offset from top of widget
 				if (this->vscroll.count == 0) {
@@ -121,6 +125,9 @@
 				}
 
 				/* Start drawing the signs */
+>>>> Comment is unclear, I'd expect something "At least one sign available." to state it is a next case w.r.t. the "No signs?" above.
+>>>> Lika above, 'start drawing' is a bit obvious in a DrawWdidget function.
+
 				for (uint16 i = this->vscroll.pos; i < this->vscroll.cap + this->vscroll.pos && i < this->vscroll.count; i++) {
 					const Sign *si = this->signs[i];
 
@@ -144,6 +151,7 @@
 	{
 		if (widget == SLW_LIST) {
 			uint32 id_v = (pt.y - this->nested_array[SLW_LIST]->pos_y - 1) / this->resize.step_height;
+>>>> just 'uint' would be enough, I think. (not a real problem though)
 
 			if (id_v >= this->vscroll.cap) return;
 			id_v += this->vscroll.pos;
@@ -162,12 +170,21 @@
 	virtual void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *resize)
 	{
 		if (widget == SLW_LIST) resize->height = max<uint>(FONT_HEIGHT_NORMAL, GetSpriteSize(SPR_PLAYER_ICON).height);
+>>>> 1. By changing *size, you can set minimal size of the widget, and thus of the window. (upon entering it has the value of SetMinimalSize()
+>>>>    and/or some basic size calculation results).
+>>>>    With most widgets, there is a small gap between the box around the content of a widget, and the widget border.
+>>>>    That distance is fixed and provided to you as 'padding'. Be sure to add it to the widget content before returning the maxdim() in *size.
+>>>> 2. I don't see a width calculation of the list widget to estimate the longest possible sign.
+>>>>    If that is intentional, it can be considered ok. If it is not intentional, plz consider what the best solution is.
+>>>>    If the answer is not to do it, a short comment with a reasoning is probably beneficial.
 	}
 
 	virtual void OnInvalidateData(int data)
 	{
 		if (data == 0) { // New or deleted sign
 			// Rebuild the list
+>>>> 1. Code style violation of comment.
+>>>> 2. Comment and code kind of say the same thing, so the former doesn't add much imho.
 			this->signs.ForceRebuild();
 			this->BuildSignsList();
 			this->InvalidateWidget(SLW_CAPTION);
@@ -177,6 +194,7 @@
 		}
 
 		this->SortSignsList(); // Try to sort the list after each change
+>>>> Comment does not add much,
 	}
 };
 
@@ -188,6 +206,7 @@
 	EndContainer(),
 	NWidget(NWID_HORIZONTAL),
 		NWidget(WWT_PANEL, COLOUR_GREY, SLW_LIST), SetMinimalSize(346, 124), SetResize(1, 10), SetFill(true, true), EndContainer(), 
+>>>> No whitespace at the end of a line!
 		NWidget(NWID_VERTICAL),
 			NWidget(WWT_SCROLLBAR, COLOUR_GREY, SLW_SCROLLBAR),
 			NWidget(WWT_RESIZEBOX, COLOUR_GREY, SLW_RESIZE),