crash if long click for few time in text

expected behavior

when users enable the feature reading temporary textshould the user still be able to copy the text that has been in the previous copies without any problem

actual behavior

when the user activates the temporary text reading feature then the user presses long on the text to copy the text several times, the application crashes and stops by itself

how to reproduce

• download comfort reder app from this [link] (https://play.google.com/store/apps/details?id=com.mschlauch.comfortreader)

• launch the app

• load txt file or fdf file

• enable feature reading temporary text

• back to home page and then click ong click for few time at the text and note fthe app will crash and stop by itself

browser ; comfort reader v 1.9.4
device ; android 5.1 idos

github repo

https://github.com/mschlauch/comfortreader

bugs recording

logcats file to help develepor to fixe it

Process: com.mschlauch.comfortreader, PID: 13712
java.lang.StringIndexOutOfBoundsException: length=12; regionStart=25; regionLength=-13
    at java.lang.String.startEndAndLength(String.java:504)
    at java.lang.String.substring(String.java:1333)
    at com.mschlauch.comfortreader.NoteComposer.getExtract(NoteComposer.java:39)
    at com.mschlauch.comfortreader.NoteComposer.getPrefix(NoteComposer.java:110)
    at com.mschlauch.comfortreader.NoteComposer.getcomposedNote(NoteComposer.java:128)
    at com.mschlauch.comfortreader.FullscreenActivity$6.onLongClick(FullscreenActivity.java:296)
    at android.view.View.performLongClick(View.java:4830)
    at android.widget.TextView.performLongClick(TextView.java:8720)
    at android.view.View$CheckForLongPress.run(View.java:19858)
    at android.os.Handler.handleCallback(Handler.java:739)
    at android.os.Handler.dispatchMessage(Handler.java:95)
    at android.os.Looper.loop(Looper.java:135)
    at android.app.ActivityThread.main(ActivityThread.java:5376)
    at java.lang.reflect.Method.invoke(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:372)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:947)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:742)```