docs: README typo fixes (#907)

Author: nb183

docs/activity-startup.md

@@ -29,11 +29,11 @@ Activities are started by [Call activity manager `am`](https://developer.android
 
 The full error description usually looks like `'java.lang.SecurityException: Permission Denial: starting Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10200000 cmp=com.mypackage/.myactivity.MainActivity launchParam=MultiScreenLaunchParams { mDisplayId=0 mBaseDisplayId=0 mFlags=0 } } from null (pid=11366, uid=2000) not exported from uid 10191`. Such error might be the indication of the fact that the combination of application package and activity name, which has been passed to Appium as `appPackage`/`appActivity` (or auto detected implicitly), is not the correct one to start the application under test. As a solution, it is necessary to check the correct values with the application developer and test them manually first by executing: `adb shell am start -W -n com.myfixedpackage/.myfixedactivity.MainActivity -S -a android.intent.action.MAIN -c android.intent.category.LAUNCHER -f 0x10200000`. If this commands succeeds manually and starts the necessary application on the device then it will work for Appium as well.
 
-Some devices might require customization of the security configruation in the developer options, or security preference. For example, Realme devices require [_Disable Permission Monitoring_ and a couple of flags in the developer options](https://github.com/appium/appium/issues/13802#issuecomment-702789411) to avoid the _Permission Denial_ error.
+Some devices might require customization of the security configuration in the developer options, or security preferences. For example, Realme devices require [_Disable Permission Monitoring_ and a couple of flags in the developer options](https://github.com/appium/appium/issues/13802#issuecomment-702789411) to avoid the _Permission Denial_ error.
 
 #### com.myactivity or com.myapp.com.myactivity never started
 
-Thus exception usually indicates, that the first application activity is not the same package/activity, as it is set (or auto detected) by `appWaitPackage`/`appWaitActivity`. Such error normally happens in applications having multiple activities. In order to resolve the problem one should check with application developer regarding which activity/package is the very first one that appears on application startup. The currently focused activity name might be verified using the `adb shell dumpsys window windows` command mentioned above. Also, Appium allows to use wildcards while setting `appWaitActivity` value. This might be particularly useful if the activity name is generated dynamically or it is not the same all the time. For example `com.mycomany.*` will match any of `com.mycomany.foo`, `com.mycomany.bar`.
+This exception usually indicates, that the first application activity is not the same package/activity, as it is set (or auto detected) by `appWaitPackage`/`appWaitActivity`. Such error normally happens in applications having multiple activities. In order to resolve the problem one should check with application developer regarding which activity/package is the very first one that appears on application startup. The currently focused activity name might be verified using the `adb shell dumpsys window windows` command mentioned above. Also, Appium allows to use wildcards while setting `appWaitActivity` value. This might be particularly useful if the activity name is generated dynamically or it is not the same all the time. For example `com.mycomany.*` will match any of `com.mycomany.foo`, `com.mycomany.bar`.
 
 #### Command '…' timed out after X ms
 
@@ -44,4 +44,4 @@ There might be also situations where an activity does not return the control to
 
 #### java.util.concurrent.ExecutionException: com.google.firebase.installations.FirebaseInstallationsException
 
-`firebaseinstallations.googleapis.com` sends the apk's certificate information as the header `X-Android-Cert` in its initialization step. Appium UiAutomator2 driver resigins the application under test with the default Appium debug signature. It causes an exception, `java.util.concurrent.ExecutionException: com.google.firebase.installations.FirebaseInstallationsException`, when the application under test starts. To avoid the exception, the session must have `noSign: true` capability to avoid re-signing. [Unblocking Firebase Network Traffic in Modified Android Applications](https://www.thecobraden.com/posts/unblocking_firebase_ids/) explains the cause more.
+`firebaseinstallations.googleapis.com` sends the apk's certificate information as the header `X-Android-Cert` in its initialization step. Appium UiAutomator2 driver resigns the application under test with the default Appium debug signature. It causes an exception, `java.util.concurrent.ExecutionException: com.google.firebase.installations.FirebaseInstallationsException`, when the application under test starts. To avoid the exception, the session must have `noSign: true` capability to avoid re-signing. [Unblocking Firebase Network Traffic in Modified Android Applications](https://www.thecobraden.com/posts/unblocking_firebase_ids/) explains the cause more.