- Fix timeout and debugging string
- Fix check for whether `LCD_TIMEOUT_TO_STATUS` is valid
- Fix incorrect debugging message
- Make capitalization of callbacks consistent.
- Allow Touch UI to use hardware SPI on Einsy boards
- Move print stats to About Printer page.
- More generic about screen with GPL license.
- Add missing handler for power loss event
- Less code duplication on status screen and main/advanced menu; more legible
- Reorganize advanced and main menu to add more features
- Hide home Z button when using Z_SAFE_HOMING
- Fix compilation errors when certain features enabled
- Fix missing labels in UI
- Improve color scheme
- Add new preheat menus
- Fix incorrect rendering of Marlin logo on boot
- Add Level X Axis and Auto calibrate buttons
- Add local UI methods to get heater timeout state.
- Add methods to resume timed-out heaters.
- Re-enable heaters on UI temperature request.
- Make `ExtUI` show a dialog box if pause needs a button press after reheat.
- Send notifications to ExtUI for M0/M1
- wait_for_user can be non-volatile (not changed by interrupt)
C / C++ compilers don't optimize away reads of non-volatile variables when a function call is used between accesses, because *any* variable could be changed by the function call. Since `wait_for_user` can't be changed without a function call, it should be non-volatile so the compiler can optimize away cases where it is read more than once without an intervening function call.