Problems when importing settings from the link

[Alex-302]

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• Filters were updated before reproducing an issue
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AdGuard version

7.21 n13

Issue Details

Steps to reproduce:

1. Go to tacirler.com.tr AdguardFilters#199639
2. Try to import settings by clicking Import button under the table

Expected Behavior

Settings imported.

Actual Behavior

Nothing.

It is caused by:

• parameters without values - importation always fails. For example:

  &dns.filters=
  &dns.custom_bootstrap=
  &dns.custom_fallback=
  

• length of URL.
  Original length in tacirler.com.tr AdguardFilters#199639 - 2561 - not works;
  Without "parameters without values" - 2518 - not works;
  Without "parameters without values" and trimmed to 2030 symbols - works.
  So, mostly configurations that are close to the default values are successfully imported.