Fixed the check for loading the file accessibility.tcl.

Author: csaba

library/tk.tcl

@@ -535,15 +535,15 @@ if {$::tk_library ne ""} {
 	namespace eval :: [list source [file join $::tk_library $file.tcl]]
     }
     namespace eval ::tk {
-	
+
 	# Do not load accessibility.tcl if running in a safe interpreter,
-	# under XQuartz on macOS,  or if Tk on X11 was compiled without
+	# under XQuartz on macOS, or if Tk on X11 was compiled without
 	# accessibility support. These cause interpreter failures or Tk to
 	# crash.
-	if { (![interp issafe] && [info exists ::tcl_platform(os)] && \
-		  !($::tcl_platform(os) eq "Darwin" && [tk windowingsystem] eq "x11")) || \
-		 ([catch {set r [tk::accessible::check_screenreader]}] == 0 && \
-		      ![string match -nocase "*warning*" $r]) } {
+	if {![interp issafe] &&
+		!($::tcl_platform(os) eq "Darwin" && [tk windowingsystem] eq "x11") &&
+		![catch {tk::accessible::check_screenreader} r] &&
+		![string match -nocase "*warning*" $r]} {
 	    SourceLibFile accessibility
 	}
 	SourceLibFile icons