Fix mobile progress bar previous/next chapter button hover/disabled visibility

CHANGELOG.md

@@ -10,6 +10,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 
 - (**Reader**) Fix scrollbar appearing with "fit to widt/height/screen" page scale mode and applied safe area insets
 - (**Reader**) Fix wrongly positioned mobile progress bar current page indicator
+- (**Reader**) Fix mobile progress bar previous/next chapter button visibility on hover and while disabled
 
 ## [20260509.01] (r3147) - 2026-05-09
 

src/features/reader/overlay/progress-bar/mobile/MobileReaderProgressBar.tsx

@@ -255,6 +255,12 @@ const BaseMobileReaderProgressBar = ({
                         sx={{
                             backgroundColor: (theme) => theme.alpha(theme.palette.background.paper, 0.85),
                             boxShadow: 2,
+                            '&:hover': {
+                                backgroundColor: 'background.paper',
+                            },
+                            '&:disabled': {
+                                backgroundColor: (theme) => theme.alpha(theme.palette.background.paper, 0.85),
+                            },
                         }}
                     >
                         {getOptionForDirection(
@@ -328,6 +334,12 @@ const BaseMobileReaderProgressBar = ({
                         sx={{
                             backgroundColor: (theme) => theme.alpha(theme.palette.background.paper, 0.85),
                             boxShadow: 2,
+                            '&:hover': {
+                                backgroundColor: 'background.paper',
+                            },
+                            '&:disabled': {
+                                backgroundColor: (theme) => theme.alpha(theme.palette.background.paper, 0.85),
+                            },
                         }}
                     >
                         {getOptionForDirection(