Fix read-only widget appearance and focus, and keep ColorInput picks surviving a layout diff (#4423)

frontend/src/components/widgets/buttons/TextButton.svelte

@@ -75,7 +75,7 @@
 		data-emphasized={emphasized || undefined}
 		data-disabled={disabled || undefined}
 		data-text-button
-		tabindex={disabled ? -1 : 0}
+		tabindex={disabled ? -1 : undefined}
 		data-floating-menu-spawner
 		data-block-hover-transfer={menuListChildrenExists ? undefined : ""}
 		on:click={onClick}

frontend/src/components/widgets/inputs/CheckboxInput.svelte

@@ -54,7 +54,6 @@
 			dispatch("checked", inputElement?.checked || false);
 		}}
 		{disabled}
-		tabindex={disabled ? -1 : 0}
 		bind:this={inputElement}
 	/>
 	<label

frontend/src/components/widgets/inputs/DropdownInput.svelte

@@ -134,7 +134,7 @@
 		{tooltipShortcut}
 		on:click={() => !disabled && (open = true)}
 		on:blur={unFocusDropdownBox}
-		tabindex={disabled ? -1 : 0}
+		tabindex={disabled ? undefined : 0}
 		data-floating-menu-spawner
 	>
 		{#if activeEntry.icon}