Modal.js: ScrollBar tweak makes some redundant actions on sticky-top

[GeoSot]

While a modal is opened, the code tries to make some magic with padding/margin on fixed elements

Although line 459 adds paddingRight on .sticky-top and line 460 reverts this, adding negative marginRight

bootstrap/js/src/modal.js

Line 460 in 0795a77

this._setElementAttributes(SELECTOR_STICKY_CONTENT, 'marginRight', calculatedValue => calculatedValue - this._scrollbarWidth)

bootstrap/js/src/modal.js

Line 459 in 0795a77

this._setElementAttributes(SELECTOR_FIXED_CONTENT, 'paddingRight', calculatedValue => calculatedValue + this._scrollbarWidth)

Replicate:

• Go to docs/modal
• Open the modal. The <nav class="bd-subnavbar py-2" aria-label="Secondary navigation"> is stiky by css, but it will not be affected at all while modal opens.
• Then add the sticky-top class <nav class="bd-subnavbar py-2 sticky-top" aria-label="Secondary navigation">
• open the browser inspector
• open the modal again

Result:

The nav element will have two js-added properties

padding-right: 17px;
margin-right: -17px;

Example test attached:

Ps: The same issue, lives in scrollbar.js too, as it is a copy of modal code

[GeoSot]

Below we can see the two defferences

css sticky-top

class sticky-top

I do not know if this counts like bug or not.