[Not a duplicate] Unpredictable Input From iOS Virtual Keyboard

Checklist

• I am reporting an issue in existing functionality that does not work as intended
• I've searched for existing GitHub issues

Description

Input from the virtual iOS keyboard becomes unpredictable and very inaccurate when there's a lot of text in the input field. After crossing a certain word threshold, which the length of depends on, presumably, a device's computing power, I have to slow my typing speed to be able to write single words, or, otherwise, random gibberish gets produced.

On iPad Mini 2 (Retina) running iOS 12.4.5 5 paragraphs of Lorem Ipsum dummy text is enough to make writing a message impossible or, otherwise, a very tedious, error-prone task. While newer devices' word thresholds are unlikely to be reached by anyone, they still exist and will decrease in length over time as iOS becomes more demanding.

Expected Behavior

Telegram can handle paragraphs of text in the input field without affecting the user experience.

Actual Behavior

Typing long messages becomes unbearably slow and difficult.

Steps to Reproduce

1. Go to https://lipsum.com/
2. Generate 5 paragraphs of Lorem Ipsum and paste it into the input field in Telegram running on an iOS 12 device equivalent to the undermentioned iPad.
3. In addition to the pasted text, type a sample text using the iOS virtual keyboard to trigger/observe the bug.

Environment

Device: iPad Mini 2 (Retina)

iOS version: 12.4.5

App version: 5.15.2

No files, tests, or entry points are identified in the report. Reproduce the issue with five paragraphs of text on an iPad Mini 2 running iOS 12.4.5, then trace the affected message input path; done means long messages remain responsive and accurate while typing.