Here's a colour-coded chart of the various unexpected behaviours present in the most common HUD layout (4 skills): https://i.imgur.com/cYYnoEP.png


Alt-clicking anywhere in the red or green areas results in a ground ping at the cursor's location.

Alt-clicking anywhere in the green areas when a skill point is available will spend the point (note the 1-pixel gap between 2nd and 3rd skills- this spacing is the same for all heroes using the default 4-skill layout, and is not influenced by the presence of passive skills).

Alt-clicking anywhere in the orange-shaded area when a talent is available brings up the talent tree (note how far down the HUD this extends).

Hovering the mouse over the one-pixel-wide white line to the right of the talent tree displays the tree, even when a skill point is available for a talent (the boundary to display tree on hover is one pixel wider than the click-box that covers it when a talent is available).

Alt-clicking the above white line results in the same output as alt-clicking either the experience/level display or the talent tree when no skill points are available- even if a skill point is available.

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I spent more time than I anticipated making that image, so I'll also just say that Invoker and Morphling have even more issues, along with other 6-skill heroes. A quick glance:


The clickbox for Invoker's spell list is larger than the box which changes the button's appearance when the mouse is over it, meaning you can click on the button without it lighting up as it does when you mouseover it (why are these two separate objects? Could the functionality that highlights the button on mouseover not be placed on the same object responsible for opening the spell list when clicked? Can Panorama UI not handle the same object having multiple functions?)

Morphling's custom Str/Agi slider can be entirely clicked through, making him the most susceptible hero to accidental/unintended ground pings.

All heroes who do not use the standard 4-skill HUD layout have gaps BETWEEN their ability icons, as well as the 4-skill layout's gaps between items, health/mana bars, etc. making them far more susceptible to unintentional ground pings.

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I would suggest placing an object with the same behaviour as an empty inventory slot under all other HUD objects to catch pings invoked from the highlighted areas, or - better yet - expanding the clickboxes for pingable HUD elements to make it impossible to alt-click the HUD without generating some sort of chat display- at least eliminate the gap between the HP and mana bars, and resize the talent tree's clickbox.