Currently, Huawei GR5 2017 features an advanced functionality known as 'screen overlay'. This developer feature causes a lot of inconvenience to users.
Here's how to turn off screen overlay on Huawei GR5 2017:
Step 1: Developer options.

Step 2: Limit background running.

Step 3: No background processes running.

Step 4: Turn off Developer options.

So you've successfully disabled screen overlay on Huawei GR5 2017. Best of luck to you all.
Read more:
>>> Guide to auto-connecting wifi on Huawei GR5 2017 without needing to manually turn it on
>>> How to lock apps with password on Huawei GR5 2017
>>> How to disable screen overlay
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