URL: https://m.check24.de/handyvertrag/htc-u-ultra?data_included=2000&young_tariff=all&hardware_nature=189&brands=htc&models=189&orderby=empfehlung_preis

Browser / Version: Firefox Nightly Mobile 63.0a1 (2018-07-12)
Operating System: LG G5 (Android 7.0) 1440 x 2560 pixels (~554 ppi pixel density)
Tested Another Browser: Yes

Problem type: Design is broken
Description: The bottom borders of drop-down menus are not visible
Steps to Reproduce:

1. Navigate to https://m.check24.de/handyvertrag/htc-u-ultra?data_included=2000&young_tariff=all&hardware_nature=189&brands=htc&models=189&orderby=empfehlung_preis
2. Tap on “Alle Filter” button.
3. Observe the bottom borders of the drop-down menus.

Expected Behavior:
The bottom borders are visible.

Actual Behavior:
The bottom borders are not visible.

Notes:

1. Not reproducible on Chrome 67.0.3396.87
2. Reproducible on Firefox Release 61.0.
3. Screenshot attached.
4. Fixed when rule height: 13.88888889vw; is deactivated:

[_nghost-c32] {
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
    cursor: pointer;
    outline: 0;
    border: 1px solid #8a8484;
    -webkit-tap-highlight-color: transparent;
    display: block;
    height: 13.88888889vw;
    -webkit-box-sizing: border-box;
    box-sizing: border-box;
    background: #fff;
    border-bottom-width: 1px solid #120707;

Affected area

<div _ngcontent-c29="" class="box">
	<label _ngcontent-c29="">
        Rufnummernmitnahme
    </label>
	<!---->
	<!---->
	<!---->
	<!---->
	<c24-filter-form-dropdown _ngcontent-c29="" _nghost-c32="" class="ng-star-inserted">
		<select _ngcontent-c32="" id="rnp" class="ng-untouched ng-pristine ng-valid">
			<!---->
			<option _ngcontent-c32="" value="0: egal" class="ng-star-inserted">Egal</option>
			<option _ngcontent-c32="" value="1: yes" class="ng-star-inserted">Ja</option>
			<option _ngcontent-c32="" value="2: no" class="ng-star-inserted">Nein</option>
		</select>
	</c24-filter-form-dropdown>
	<!---->
</div>

Watchers:
@softvision-sergiulogigan
@softvision-oana-arbuzov

sv; country: de

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